A bunch of Windows xp problems

It all started when I tried to access Frontpage and got a message
stating "preparing to install". Tried to work around it several times
and then gave up and went to add/remove software. I couldn't remove
it. I restarted to safe mode and then removed Frontpage from my
computer.

Restarted and tried to reinstall and NO. I go this message"

The windows installer service could not be accessed. This can occur if
you are running windows in safe mode (no I am not) or if the windows
installer is not correctly installed. Contact your suppor personnel
for assistance""""

The Microsoft Word started this problem, then Outlook express.

What virus or malware is doing this?