If you're moving on the stills with motion effects, and do them without making the image size exceed 1920X1080, then edit them in a ProRes 4:2:2 sequence set to be at 29.97, and then compress that HD version to an SD DVD in DVD SP. It's a garbage in/garbage out situation. Send that whole sequence to Motion for the titles or use Title 3D for them. The text tools in FCP are bitmapped, but those Title 3D titles are not. They'll hold up better. Making them larger rather than smaller will help preserve them too when you compress for that DVD's SD file set.
8-Core 3.0 Intel Mac Pro, Dual 2 gig G5, AJA Kona SD, AJA Kona 2, Huge Systems Array UL3D, AJA Io HD, 17" MBP, Matrox MXO2 with MAX - Cinema Displays I have a 22" that I paid 4k for still working. G4 with Kona SD card, and SCSI card.