Constant errors in different software after a crash

Hi there!

I was installing Photoshop CS4 (done it a few times before on this system, all as usual), had some software running too. Suddenly the installer crashed and i got a whole lot of different errors from different software. It looked like all the processes that were running at the time got somehow corrupted. I reinstalled my Windows a few days before this happened, so I got not much to lose and i reinstalled the windows again, making a full format of the system drive. After windows got reinstalled, I downloaded clean fresh installers of the programs that were giving me those errors during the crash, installed them and they gave me those errors again. What on earth could have happened so that the errors keep appearing after a fresh reinstall of Windows on a freshly formatted drive and installing the software with a freshly downloaded installer?
The errors I'm getting are completely different. Google Chrome gives me "application failed to initialize properly (0xc0000005)" error, i've found a fix for that and it worked (but it never happened before and now it happens even after format\reinstall). .NET Framework installer says "Microsoft .NET Framework 3.5 SP1 has encountered a problem during setup. Setup did not complete correctly.", some other software report corrupt files problem (even with freshly downloaded files). Tried checking the hard drive, no problems found.

Running Windows XP 32bit on Core2Duo E8500, 6gb RAM = 2x2gb + 2x1gb (3.25gb according to XP), Gigabyte EP45C-DS3 MB, 3 SATA hard drives (750gb Seagate, 2x Samsung for 250gb & 1tb), GeForce 7600GT 256mb.

Any ideas? I'm confused.

I had a suspicion that my hard drive may cause this, maybe some kind of virus in it's boot area or something (is that even possible?). So I deleted the whole partition and created a new one in it's place. And I also tried what you said. Well, something of it definitely worked, maybe my hard drive theory, maybe your settings. The problem is gone, hopefully completely. Thanks!

A few more errors so you'll get a fuller idea:

"The instruction at "0x00403f3a" referenced memory at "0x0124c598". The memory could not be "read""

"The application failed to initialize properly (0x000007b)"