Excel and Word 2007 crash at startup

Doesn't matter if I double click a document, or start the app by itself. It
will load, appear OK, and then, within a few seconds, a box appears stating
"Microsoft Office Excel (or Word) has stopped working", with the usual
options of debug, look for fix, and close.

This happened once before and I just uninstalled/re-installed and it worked
fine for <shrug> several months. I used the Microsoft Fix-it dohickey for
repairing after and update, and then followed that with a manual regedit,
still broke.

I found a few items in the word groups. When I launch "winword.exe /a", Word
opens fine, but that switch didn't work for Excel. I followed 2 guides from
those threads on "What to do when Word Crashes", but that didn't help either.
Renamed normal.dot for word, couldn't find it if Excel uses it.

I can always re-install again, but I would really like to find a real fix if
possible.

Thanks.