Disk Drives Cause explorer to crash?

[Mullesch2001]

Yesterday Finally got my pc working good again Specs at bottom of post. worked throuhg some .dll errors found a bad stick of ram, got my graphics card to stop crashing and so on i got my pc to stop crashing from .dll errors and bad ram. SFC /SCANNOW still pops up about 20 times saying bad file or whatever.( scratched xp cd beyond recongnition long time ago) but haven't ad any dll errors recently but i found out that uninstalling intellimouse fixed almost all of my problems i hate that program. so i wanted to get my dual monitor working again so i went back to insatll ati catalyst control center because i removed all ati software and just insatalled the driver a while back. so i popped in the cd went to my computer and my dvd drive didn't show up just my cd drive and my magis iso/cd drives did. so i swithed it to my cd drive, nothing. restarted and went back to my computer and still no dvd but cd drive said it found the cd but no image next to drive like it used to just aticd12-0876 so i clicked on it and "my computer" stopped responding so i ended it and screne went blank and came back a minute later.tried swithing jumpers , ide cables master and slave position everything nothing changes. This is a custom built pc.
Specs:
intel p4 3.2ghz 1mb l2cache
was 2gb pc3200 ddr ram now 1.5gb pc3200
assrock pv4bb mobo
sapphire ati radeon 3650 hd pro 512mb gddr3 agp graphics card
200gb hard drive
Hl-Dt-St Cd-RW GCE-8400b
DVd+rw lite-on dvd drive
250w dell psu
Any ideas would be great i'm almost thinking about downloading a copy of pirated windows just to fix my .dll errors but this is the only problem left on my pc