Hi, Lollie61! On the "Open Discussion" forum I bumped up a mish-mosh idea thread ("A-Jock's fave INTENSE DVD mish-moshes"), and here on the Video Discussion forum I bumped up a couple of other "Mish-Mosh" threads that should give you several good ideas for how to customize your workouts with a multi-disc player (which, by the way, multi-diskers are just the best tool ever invented).
HTH -
A-Jock