For some reason when I look at a page (like my Myspace page), my embedded YouTube videos show up as white boxes. This hadn't happened before this morning when I did an AVG virus scan and it added infected files to the virus vault. I don't know if that's linked or what. A lot of logos and hyperlinks that once worked aren't working anymore either, they just look like a small icon with a slash through them. Any help please?

I would think that you may be infected. Try these free, online scans to see:
http://onecare.live.com/site/en-us/sandbox...s%2Fdefault.htm (requires IE)
http://housecall.trendmicro.com

If you do suspect that you're infected, you may want to try posting in the "Am I Infected" forum located here: http://www.bleepingcomputer.com/forums/forum103.html

It's also possible, though not likely, that AVG removed something it shouldn't have.
What does it list in the virus vault?