After safe mode Dr Web check,cannot boot Xp even in Safe mode!

[ddsdavey]

I detected various trojans etc so ran a registry cleaner but some still remained so i booted into safe mode and ran a deep scan with Dr Web and cured issues but suddenly i got a blue error screen "crql not less or equal",that old chestnut!
My system would not boot into Windows (Xp prof. corporate) and after lots of various attempts decided yo try and "repair" Windows via the installation disk option.So off it went,copying all files etc. but then only got to a certain point and was halted with a message stating Disk 0 at i.d. 0 at bus 0 and something atapi
(sorry,it moved so quick i didnt write it all down but there was not much more than ive mentioned).Again after several attempts with nothing i started taking drastic action and decided to just try a full re-install after formating the drive but again it would not let me.
To cut a long story short,my pc boots up and gets to the initial "Windows Xp" loading bar but then freezes and reboots and does this in and endless cycle! I cant reinstall Cause it wont let me and there seems to be nothing in the Bios menu that can help???
I dont know what else i can try,how do i get Windows running again if it point blank refuses? I know it is only through stupidity that i have erased something important but i dont understand why it would prevent me doing a restore/repair or full reinstallation and i have had a fair few problems over the years but nothing like this,that simply prevents me from accessing anything.
I would really appreciate some help if anyone is willing.Im new to the forum so please accept my apologies if this is a little long or i am a little vague!
The BSOD error is:
0x00000018,0x00000002,0x00000000,0x80826976.
Cheers.