windows dvd maker

Hi,
I have vista home premium, and wndows movie maker has stopped working, it
opens but when I click on add files, it turns all cloudy and DEP shuts it
down, can I repair this? as well, I can not uninstall a couple of programs
that are not orking either, like itunes, I keep getting the message to get
aahold of the system admin. I am using an admin acct, any ideas?
Thank you
Leanna