PC foolin around. HELP!!!!!

[armourlength]

I have a Athlon 2600+ on Asus A7V8X SE MB with 256 MB DDR 333MHz RAM OS is XP PRO SP2
For the past 1 month the PC freezes occassionally when slightly memory intensive work like running multi apps, audio editing & playing Midtown Madness bundled with Digit Jun 05.
Once it freezes I restart & then too it freezes while running scandisk or during startup.
Since yesterday its become very frequent & I can't do anything on it.
Rt now it said It couldn't load the user profile (ADMIN)
and sent me to default profile. Where too it froze when I ran chkdsk from RUN... as some files were corrupted & the bubble keeps popping up.
Pl help me as I feel its some thing to do with the RAM being faulty ( its a yr old RAM) Check out the problems I have been facing:-
Here's a summary of some more problems:-

1. NAV 2003 freezes when doing complete system scan.
2. Defragmentation of C: doesn't take place even after 2 hrs (10GB partition) It remains @ 10 - 15%
3. Recently an error has started cropping up after I close IE 6.

iexplore.exe - Application error
INSTRUCTION AT "0x0190e10" referenced memory at "0x0128ad58". The memory could not be read.
Click OK to terminate the program.

What cud be the prob. There's no overheating prob..

[Ringwraith]

Somethings u can try:
1. try installing new drivers ...if that doesnt work reinstall windows
2.open ur cabinet...check temperatures of the cpu/ram/harddisk, also clean ur components of dust etc.
3.ur motherboard capacitors might be damaged...this usually happens due to cheap components being used/faulty power supply

[mohit]

it could also be that ur hard disk is losing its life. get it checked for bad sectors. i suggest u completely format all partitions and reinstall windows. do the above suggested by ringwraith also. hope it helps. and i hope u r using a good UPS also. Power fluctuations can cause seriouse damage to your pc. take care.