Try this:

Go to Start->Set Program Access and Defaults->make sure that the default virtual machine for Java is NOT Microsoft Virtual Machine.

If you still have a problem after that, maybe you should run a full scan for spyware/viruses, run scandisk/chkdsk (WinXP). Uninstall, clean the registry and reinstall..

Else, I dunno.

If you want the URL where to get good antispyware and antivirus, disk defragmenter (WinXP Default defrag sucks!), registry cleaner programs just email/PM me.