All Exe files are associated with Windows Media Center

Got one here for everyone to puzzle on. All my executable files are
associated with Windows Media center. And I mean all. I try to personalize my
settings, windows media center opens, I try to go to windows updates and
recieve this prompt:

A website wants to open web content using this program on you computer.
Media Center Allow or do not allow.

The only thing that I can do is Internet Explorere. Everything else trys to
open in media center. I can get to the control panel and file associations
there, and try to make file types open with a certian program, but all the
..bat, .com, dll, ect say unknown program and I have no idea what program to
associate them too. And exe is not even listed. There is no open with when
right clicking either.

Sure am in a pickle and ideas. I do not even know how the association got
changed.