a VERY bad case of the Stop 50 on XP pro

My system is:
XP Pro service pack 1
2 hard drives, IDE
2 memory cards, 256 mb each
ps2 mouse and keyboard
Athalon computer, 2GHz+

I've been having a rough patch with my computer lately. Without having installed any new hardware, or driver, it stopped booting properly. Last thing i remember before i restarted it when it functioned for the last time, was my opening a video file in Winamp and the playback acted up by skipping about. I rebooted.

When it boots past the BIOS phase, i get the menu which tells me windows didn't boot properly, so i can choose safe mode, with networking, normal boot, last known good configuration etc.
after any of these, the computer resets automatically. With the normal boot and last known good configuration, it runs checkdisk and THEN resets automatically.

I tried accessing the computer via ERD Commander 2005, and it tells me PAGE_FAULT_IN_NONPAGED_AREA, along with Stop 50 (0xe0b7b4e8, 0x00000000, 0xe0b7b4e8, 0x00000000). no more info than that.
I've also tried swapping the ram as some sites suggested for this error, and even removed ram, it made no difference. Basically i can't get into windows so i can't reinstall windows. I even tried the xp installation disk, i get the same error when i try the recovery console. If i try to reinstall, it gives me the stop message as well.

With knoppix Live however i was able to access windows, i ran a memory test and the memory appears functional. I booted the knoppix desktop and i can see that i have access to my hard drives, so those aren't messed up and neither is the ram.

Does anyone have any ideas how i can get my computer working with windows xp without having to reformat the entire harddrive (not that i have the opportunity to do so as you've heard). Someone mentioned on a forum that i might want to delete the swap file as a generic resolution to the stop message. Thing is i can't even see the pagefile.sys with Knoppix live, and i enabled showing hidden files. So either i need to do something more to see the file, or it's just not there.

Thanks alot for your time guys
MIchael