There's an egalax USB touchscreen driver in the Poseidon package, so that opens up a few more screen options. As far as games go, I don't think there will be too many mouse-only options. Megaball comes to mind.
Lemmings and graphic adventures (Indy Fate of Atlantis, Simon the Sorcerer) are also possibilities, but because they bang the hardware the touchscreen drivers won't work.