Has anyone had crashes during OS X software updates?

Question

Recently, I've updated my MacBookPro to OSX 10.7 .  After a few weeks, the software update program notified me that I had an install pending (security updates, JAVA update and 1 more I think).  I dutifully downloaded the updates and Software Update told me that I had to restart the computer.  So I did.  The computer restarted and began with the "Installing Updates" message and progress bar.  Part way through the install, the process hung.  An hour later it was still at the same place.  Had to leave so shut down.  Now can't the computer to start normally.  Attached it to home computer via Target Disk mode and used disk utility, but still no luck. 
Then today I was reconnecting a old iMac running OSX 10.5 to my home network.  All started up normally, I was again notified by software update to install the OS Security update and JAVA updates.  After the download and the restart, the install progress bar started up.  1/4 of the way through the entire process hung again!  Now this iMac is also unable to start! 
So 2 of 3 computers are now out of commission because of installing updates that did not install properly.  How very very frustrating.  I have now experienced this twice.  Has anyone else out there had this issue?  Any recommendations?  Because it seems that  no one knows anything about how to fix this issue except to wipe the disks, reinstall the OS and lose all the data.  Help!
HJO
PS  Now I'm trying to connect the laptop to my last working computer via target disk mode to copy off the document files, and the transfer is hanging up  somewhere in the Firewire system.  I got a vew files over but it has taken hours and hours.  Aaaarrrrgggghhhh.  

Answer 1

Well don't update your last computer.
I suspect there is a problem with your router/home network, perhaps it was compromised or the router is failing.
Some older routers have a file size download limit, I think it was old Rogers routers if I recall, I've seen this problem here before, it just cuts off after a certain limit.
So here you go updating and the file download is not complete and bricks your machine.
also 10.5 is outdated and insecure, you need to get the files off that machine and call Apple for the 10.6.3 white retail disks if it's a Intel Mac.
I would consider all your machines and network compromised and requiring full resets of everything to leave no stone unturned.
I would get a new router,  make it super secure first apply it's firmware updates and very secure WiFi (WPA2 AES), test the Internet connection and your ISP speeds are whay your paying for.
Then data recovery on each machine, then wipe and install OS X (10.6.8 at least) on each and then use ClamXav to scan the possibly infected files and vet them before returning to the cleaned machines.
Don't use any sort of migration or TimeMachine business, just bare bones files that don't have executable code.
It's ok, all this can be fixed. All files recovered and everything back to normal.
Break the job up and tackle each piece, or if your not willing, call in a local PC/Mac specialist, they will fix you right up.
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