When I tried ctrl+alt+del, I get the "task bar disabled by administrator" message.?

You might have success using one of the methods recommended by this Microsoft MVP.

http://windowsxp.mvps.org/Taskmanager_error.htm

I had the same problem last year and it turned out to be a virus. Even though I was running a current AV program it still managed to slip through. Here's a few free AV programs you might want to use to run extra scans if your own AV programs comes back clean.

http://free.grisoft.com/doc/2/lng/us/tpl/v5

http://www.avast.com/eng/free_virus_protectio.html

http://www.free-av.com/

wwbgd