My computer is Acting Very Strange :(

I'm posting this in the malware section, but I'm not even sure if it is.

Last night my computer (Windows XP SP2) developed four new problems.

(1) it takes a long time to boot - the hangup occurs just before I am requested to type in my password in order to open the desktop. It takes a few minutes instead of a few seconds;

(2) Add-Remove Programs opens but will not populate;

(3) CCleaner hangs almost immediately after it begins to clean;

(4) My computer > Right Click > Properties takes a long time to open. Other right click functions of My Computer have no obvious problems.

Running AVG Free.
AdAware did not find anything.
Spybot found ClearSearch.net in:

Autorun settings(ALUAlert)
HKEY_USERS\S-1-5-18\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\ALUAlert

and in:

Autorun settings(ALUAlert)
HKEY_USERS\DEFAULT\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\ALUAlert

Trojan Hunter found nothing.

I did one thing I have not done in a long time right before the problem began. I played a DVD - a brand new Warner Brothers - in the computer which is having the problem. This may be significant because of the timing. This may also be significant because a while back I played a different new Warner Brothers DVD and I permanently lost the ability to run ONE program on my computer (Roxio).

Of course, the DVD playing may be purely coincidental. I just don't know.

Any suggestions as to how I should proceed?

OK, I did some investigating. It just took a long time for Recycle Bin to open. The flashlight was hunting for it for a minute. When it finally opened it took a while for me to be able to empty it. I went back to CCleaner. If I UNchecked "Empty Recycle Bin", then CCleaner worked fine. So it appears that Recycle Bin is the problem, not CCleaner. It also seems to take forever for Notepad to open as well.