I have a couple of games I want to finish, but I don't know which to start with ( the shortest)
Here are the games
Saints Row 3
Prototype
RE 5
and Civilization Revolution.
From beginning to end what is the shortest game on the list?
RE 5 is most likely the shortest. Prototype might be faster than RE 5 if you muscle through the main story and don't worry about everything else, but I'd put it as second. Saints Row 3 would be third. I haven't played Civilization Revolution.
Civilization revolution would probably take you the longest simply because it's an RTS. I'd say to play through Prototype first, then RE 5, then either Civ or Saints Row for last.