Combining DVDs

I have about 15 DVDs, each with one about 10 min short film on them (mostly from college film classes). I hope to combine these into one DVD.

What would be the easiest way to do that?

If I were you, I would rip the DVDs with DVD Fab HD Decrypter, demux them with PGCDemux, and use DVD Lab Pro (fully-functional thirty-day trial available) to author a new disc with a basic menu enabling you to select which short film you want to watch.  I do not know if there is an even easier way, but this is a relatively straightforward process, as far as I am concerned.

Glue?

Duct Tape?