Downloading Flash Player plays advertisement -- and installs a virus?

Question

I've had this problem 3 times consecutively trying to restore my system after it was destroyed by what seems to be a virus.  It took that many tries before I realized the in-your-face advertisement and problem process are coming from Adobe itself.
THE PROBLEM
The apparently viral process runs as SVCHOST and uses the RasMan (remote access manager) service, apparently to transmit the contents of your hard drive to someone across the internet.  It takes 99% of CPU, 1/2 Gig of memory, a lot of disk activity, and high transmit volume with low receive volume over the network.  Unplug the network, and the SVCHOST falls to about 35% CPU with more intermittent disk activity.  Plug the network back in, and it climbs back to 99% with high disk activity, and high transmit volume.  It seems clear that it's copying the hard drive out to the network.  Before I realized that, I thought it might be an internal process and just let it run to get it over with.  It just got worse, finally running the machine out of memory and making it almost too slow to terminate the SVCHOST.  When I finally did terminate it, the machine returned to normal.
WHY I THINK IT COMES FROM ADOBE
I restored my system to a known clean state from a disk image.  I've done that 5 times now.  The first thing I do on booting the restored system is wait and check for that process -- it's not there.  Next, I update Firefox, then wait again.  No problem, as long as you don't click on the Update Flash Player link.  Then you click on that link, and immediately there's a pop-up and it plays audio saying "You've won a free Xbox", or else some other advertisement -- it's not always the same -- and also opens a tab to a site outside of both Firefox and Adobe.  Some advertising site.  So, I first thought I'd been spoofed by a false advertisement and unwittingly clicked on a malicious ad banner.  Restored the system again, and next time went directly to Adobe.  Clicked the link to download Flash Player, and... immediately, a similar ad popup and tab appeared, and it played a "congratulations!  .... you've won ____" audio clip.
Right after each incident where the ad appeared, the computer began bogging down with disk activity and high CPU consumption by that SVCHOST process, and apparently copying out the hard drive to the internet (high network transmit activity).
IT'S NOT THE PLAYER ITSELF
I never even got around to downloading and installing the player.  The trouble started right after that ad popping up.
CONCLUSION
So, Adobe has sold out.  Not only is Flash responsible for most viruses transmitted, now just to get the player Adobe itself is shoving an obnoxious ad in our faces which installs a trojan.  A Malwarebytes scan before the Adobe-shoved ad came up clear.  Another scan after the Adobe-shoved ad detected a trojan and attempted to remove it, but it just comes back every time you restart the machine, and copies your business machine's hard drive out to the network.
So, Adobe, who has obtained copies of my business's intellectual property (I'm a software developer) and financial records, as well as sensitive data such as accounts and passwords?
CONSEQUENCES
Incidentally, this came at the moment when I was transitioning from developing native applications for desktop and mobile platforms.  It was my intention to transition to using Adobe Flex for most work in the next few years at least.  I had the Flash Builder on two of my systems, and was starting to work with it.
But this incident, combined with numerous past incidents that have made me absolutely hate both Flash and Adobe, was the final straw.  I have deleted all Adobe products from all of my systems, and will not be using Adobe Flash or Flex or any other Adobe products for development or anything else.  Now I understand why Steve Jobs also dumped Adobe -- it's nothing but a viral company!  Adobe itself is like a virus.
Thanks for wasting a day on a holiday weekend trying to restore my system just so I can resolve a minor customer issue.  Thanks, gals.  Hope you enjoy the millions you get from that advertisement, but in my case it caused me to return to native development for all platforms instead of using Flash, Air, Flex, or any of the other viral stuff you use to invade 99% of all systems on the planet and then shove ads and more spyware on us.
I've also uninstalled Photoshop.  (The uninstallation took 45 minutes.)  I can just use GIMP, it's good enough now.  Adobe = BANNED, because all that Adobe stands for anymore is VIRAL.
Thanks again

Answer 1

Thanks for the reply.  I forgot to include:
-- Windows XP SP3 (32-bit) running on a 1.9 MHz Turion X2, with 2G memory
-- Already-installed Flash version was 10.x, I think 10.1, but hadn't been updated for months since it was a restored backup.
-- Firefox 3.6.13, just updated to 3.6.18   (yes, I've tried 4.0, it was slow and annoying, so I went back)
-- Other software on the machine: Microsoft Office, development tools (Visual Studio, Eclipse with Andriod and RIM plugins, BlackBerry JDE, Sun Java SDK, Firefox, Adobe Photoshop, GIMP, Adobe Reader, Adobe AIR, Adobe Shockwave, Flash Builder, and a few old trusted versions of minor utilities such as WinZip, DivX, Grep, etc.)
-- Only changes for several months were:  Installed Flash Builder, updated Firefox, tried to update Flash Player
I only reacted this way because I've lost SO MUCH time and also data, adding up no doubt to YEARS of time, primarily because the platforms of two companies (Microsoft and Adobe) are like warm, moist, undressed flesh wounds that just invite every kind of infection to enter and flourish.  It's not just their prevalence, it's their design.  For example, why can a Flash program insert native code into a SVCHOST, when it's nearly impossible to figure out what's running in the SVCHOST, what it's doing, where it came from, and how to kill it permanently?  That just creates conditions favorable to malware.
Anyway, after restoring my system to a snapshot of a known clean state, I first selected Check for Updates in Firefox, it downloaded it update.  Then I unplugged from the net before letting it restart and install, and it did its thing.  Then I plugged back in and went directly to www.adobe.com, selected Flash Player under Downloads, clicked Download Now, and then up popped the advertisement right after the click.
Previously, I let Firefox finish its update still plugged in -- it took me to their site, where a banner appeared saying Flash needed to be updated.  I clicked that, and a similar ad popped up (for a different product, and using a different URL, but the same type of thing -- an instant audio message and a new tab plus a small pop-up.)
So it seems clear that Adobe has decided to make some extra millions by forcing everyone who downloads Flash Player (at least from a Windows machine last night and this morning) to hear "Congratulations!  You've just won an imaginary Xbox 360 in compensation for letting our ad partners copy your hard drive and pay us money at your expense -- you thought Adobe would just give you a Player for free?!  If you're further stupid enough to try to claim your imaginary prize, just enter more personal information, as well as the address and phone number of your girlfriend, because what Flash is all about is invading the home, popping up and penetrating the market by force, never really taking NO for an answer -- we'll just starve her and keep asking until she says Yes."
Ruthless advertising is just completely out of control on the internet.  When you show up on the site of a major company and get hit with an obnoxious scam pop-up ad that's just like something you'd get from making the mistake of visiting some unknown website -- you know, the kind that escape the borders of the window and say you've just won a million dollars, and that are usually followed by a phony "virus scanner" taking over your machine any moment -- then internet ethics have been completely overrun by the glut for advertising money and collecting valuable information from users.
Can't BELIEVE I got a pop-up ad and spyware from trying to download Flash Player directly from Adobe's site, what is this company coming to?  I don't remember the details exactly, but there was some other instance -- with Reader, I think -- where they were bundling spyware with it, and doing it in a way that you would not realize it would be installed, and then it was hard to get rid of completely.  There was a big row about it, and I remember having to restore my system multiple times there too, to ensure no contamination.  That's why I'd gone back to an earlier version of Reader, but now I've deleted all Adobe software completely.  It is the most unethical of all the big technology companies, no-one is more ruthless or viral than Adobe.
You've got plenty of money, you're rolling in money, and you resort to stuff that crooks use to make their start-up capital?