[Christ]

full tune up, if you're not sure about the integrity of the engine... you could go so far as to check the bearings and such, but if you're going to do that, you might as well just rebuild it.

Change tbelt, water pump, plugs, wires, cap, rotor, oil, etc... FULL tuneup... something you should do every time you buy an engine and you're not sure about how it was treated/maintained.

You could get away with not replacing the timing belt, if you inspect it well, but they're so cheap, that it's not worth risking your engine.

You'll definitely want to run a compression test, if possible... it's not that hard to do tho, and you can do it somewhat well with a hi-torque drill on the crank shaft.