Sounds like you may have a bum plugin or old version?
Instead of color finale, use FCPX’s built in camera LUT system, as Marco mentions. FCPX also has some decent built in color correction capabilities as well.
Also, if you have a 100 minute DVD, you have to make sure that FCPX encodes the file small enough to fit on whatever style DVD you have (single layer, dual layer, etc). FCPX provides very rudimentary options for this. What settings do you use when creating the DVD? Have you checked to see if the file will fit on a standard DVD?