MikeFE: Using Scummvm (if you can get the games):
Sam and Max hit the Road
Day of the Tentacle
DiscWorld 1 and 2
Beneath a steel sky (FREE ON GOG!)
Indiana Jones and the Fate of Atlantis
Monkey Island
BTW: I played the above games on a 7" tablet - I'm not sure how well they can be played on a smaller screen.