|We're glad to hear you fixed your problem ! !|
Most malware these days is not a virus - it's something else - a trojan, root kit, fake symptoms created by the maker of "rogue" anti-malware programs to attempt to fool you into buying their program, etc., etc., or more than one of them at the same time.
No one anti-malware program finds all malware these days, however your no video symptom was probably not caused by malware.
XP can be installed "overtop" of an existing XP installation by booting the computer from an XP CD and following a Repair installation of Windows procedure, if you don't want to lose your personal data that you have added to the partition Windows was originally installed on - that's probably what you did.
It only deletes and replaces certain essential Windows data, often Windows works fine after running it, but doing that can't fix all problems, and sometimes you must then install Windows from scratch.
However if you still had problems after doing a Repair installation of Windows procedure, you would have had them all along, ever since then.
If you weren't having problems right after running that, there are various ways your data could have gotten corrupted since then. Running the Repair installation of Windows procedure again would probably have fixed your problem, without you losing your personal data that you have added to the partition Windows was originally installed on . You always have video when you boot the computer from the XP CD, unless your video adapter is damaged.
Your problem could probably have been fixed without having to install Windows from scratch.
Most people don't bother to copy personal data they don't want to lose (that was on the same partition Windows was installed on) to elsewhere BEFORE they install Windows from scratch, despite the fact that's not hard to do. E.g. one way is you just boot the computer from something such as a Linux disk that can read all the data on the drive and copy the personal data to CDs or DVDs or a flash drive or whatever.
What were you trying to accomplish by disabling the VGA video adapter in Windows ?
Were you having problems before that ?