This is only happenning on certain adobe pdf files, looks like version 1.4.
I was trying to download form from VA site and it would crash and also cause internet explorer to quit
Here is what I did to fix it and it worked.
Avast 6.0.1367
Behavior shield
Expert settings
Add trusted
Browse
C:\Program Files\Adobe\Reader 10.0\Reader\AcroRd32.exe
Add it and you will be ok.