I running Vista and I’m also having the "Data Execution Prevention error", I attempted to correct the problem as StormJumper explained but that was a no go.
I will just wait till the non beta FabDVD 5 comes out, till then I just use the DVDFab 5 Beta 5.0.0.0 as that build worked fine for me.

I am sure they will address and fix most of the bugs by the 1st official Build.