WinXP Pro computer keeps crashing

[hansel]

I just came back from my 2 1/2 week vacation to find that my pc is not working. Before I left, the computer was working just fine. When I came home and booted it up, the computer seemed very slow as I was opening Outlook. Then it froze. So I rebooted it and I get this error message:

svchost.exe - Application Error

The instruction at "0x745f2780" referenced memory at "0x00000000". The memory could not be "read."

So then I click "OK" to terminate the program and I try to log in to Windows. I click on the log in icon and it says "Loading your personal settings..." and it just freezes like that.

I reboot in Safe Mode and find that my E: harddrive is almost full. So I delete a bunch of files as well as some files on my C: harddrive just in case. I reboot, and Windows loads!

As I start to use my computer, I get that svchost.exe error again! On top of that, I get another error message:

Generic Host Process for Win32 Services has encountered a problem and needs to close. We are sorry for the inconvenience.

Eventually, the computer freezes and I have to reboot again.

Can somebody help me out here?

Computer Specs:
Windows XP Pro SP2
Pentium 4, 2800 MHz
Motherboard: Abit IC7
512 MB RAM
127 GB harddrive with 101 GB Free space (C:)
58 GB harddrive with 23 GB Free space (E:)

[Ob1]

start by scanning for viruses and spyware in safe mode.

www.memtest.org
download and burn the program, reboot and boot to the cd. if there are any memory errors it will display them. if no error are found the proceed below

i would run a system file checker.
start>run>type w/o quotes "sfc /scannow"
you need your xp disc to run this.

if that doesnt solve this then run a chkdsk
start>run>type cmd>type chkdsk /r