"Whenever I've seen similar symptoms they were the result of the initial installation of XP."
I concur.
"The file corruption problem starts when I'm even installing windows
(the cd is fine, formatted my other com just to test the cd)I had to retry for like 5 times to finish installing XP and now whenever I try to install new stuff to my computer I had to retry installing those files heaps of times to get it to work without error msg saying "file corruption etc" or crc error ( all the files works fine on my other computers)..."
If the CD has been verified as good (no scratches, smudges, etc), it would seem the problem is most likely hardware related. Either how it's set up in the bios, or physically related. Verify all your bios settings. The XP install should advise you of any potential problems in this area, but it only takes a couple of minutes.
Run a CDROM lens cleaner, or swap drives if you have a spare.
Go back to the board level and verify any and all power and data connections are secure. This includes the CPU, add in cards, etc. Remove and reseat the RAM a couple of times to help clean oxides from the contacts.
Test the RAM;
MemTest86
Since you've done it already (format etc), kill the hard disk with
KillDisk and let the XP install set it up.
CAUTION: Killdisk will do just that. The
ENTIRE hard disk will be blanked right back to factory levels. As low as the manufacturer allows in it's controller. It will even turn off the SMARTDRIVE on the disk.
Performing the above shouldn't take more than an hour or so, excluding the memtest time, and up to the point of installing XP. At least you'll be confident of the physical connections and eliminate some of the components as the cause.