first run ur updated antivirus and/or the above toll in
SAFE MODE. (u do have an av dont u

). clear ur pc junk with 'ccleaner'. then pls post ur hjt logfile here or at
www.hijackthis.de for analysis.
once u have got rid of ur infection, u'l have to re-enable 'registry editing' and 'folder options'
this will help u to re-enable registry edtg
http://www.faqfarm.com/Q/How_do_you_..._administrator
after this is done, to enable back the folder options :
click
http://www.kellys-korner-xp.com/xp_tweaks.htm and go to tweak number 129. download it, double click on it and add to registry. reboot.