Shoutbox

Since you are using Windows XP you could try this;
Start > Help & Support > Restore my computer to an earlier time > pick a date just before the problem started and restore to it. This way the problem should be gone, however you will undo any system setting changes from before it started (being two days it shouldn't be much if any).
Your files and data will remain safe, just software you've installed after the time and date you pick will be back to what it was when you pick the point.