Flash is Causing my Browsers to Crash. PLEASE HELP

Question

I'm not a computer expert, and I really don't know all the jargon, so I hope you all can bear with me while I try to explain what's been going on.
A few weeks ago I made the mistake (apparently) of updating my Flash Player because I got tired of that little reminder popping up.  Now, my browsers are all crashing every few minutes or so, every time any HINT of Flash shows up.  This is happening on Safari, Firefox, and Camino.  (I installed Camino out of desperation.  Now I just have an extra browser I don't need.)
So I ended up uninstalling Flash completely, and have downloaded an archived version of Flash (Flash 9), figuring that since my computer was working perfectly before the update, and works like crap after the update, then my best bet is to simply return to how things were before.  But now I can't get the stupid thing to install at all.
Here's what I have for a computer:
iBook G4
Mac OS X
Version 10.4.11 (Tiger)
Processor 1.2 GHz PowerPC G4
Memory 1.25 GB DDR SDRAM
After downloading Flash Player 9, I have a Flash Player icon on my desktop, so I know the download was successful.  When I double-click it, it opens up to show a folder containing four boxes.  There are no installation instructions, as the Adobe site claims there should be, and when I visit any sites with Flash on them (which is most of them these days) I get a message saying "plugin not found", or some such.
Here's what happens when I double-click the Flash Player icon:
On the left is a file called Flash Player.plugin with a big arrow pointing to a folder called Internet Plugins.
Under the Flash Player.plugin is another file called flashplayer.xpt with a big arrow pointing to another folder called Internet Plugins.
I have tried dragging and dropping the files from the left into the folders on the right, but all that does is make a springy sound as the files copy over.  It doesn't actually install the Flash program, and still no instructions come up as to how to do so.
At this point I'm thinking of resorting to buying a whole new OS disk, just so I can start over with a "new" computer.  I am at my wits end, because I can't visit half the sites I normally visit without Flash, but when I have Flash installed, my browsers crash over and over and over again, usually while I'm in the middle of typing an email, updating a blog, etc.  From now on, I won't be doing any updates to my plugins until I'm absolutely 100% certain that the updates are compatible with my OS and my browsers, no matter how many times the stupid thing pops up screaming at me to do so.

Answer 1

For the last couple months, every time we open the iTunes store, it causes our entire computer to go to blue screen and crash.
The most likely culprit is trouble with video drivers, as per the following document:
[iTunes for Windows: System restarts, blue screen, or quits unexpectedly when accessing iTunes Store|http://support.apple.com/kb/TS3441]
Head to the following page at Dell and enter your service tag:
http://support.dell.com/support/downloads/index.aspx
Check your downloads page. Are any updates available for your video card or display adaptor? If so, and if you update, does that allow you to visit the Store again?