Ribs are a good choice. I like to smoke for about 2 hours, then wrap in foil and go to the oven to finish. I used to get all exotic with dry rubs, but now I just do salt, pepper and a little bit of brown sugar and paprika.
A few general tips -
be sure your fire is going good before you cover it and start the smoke.
Avoid the temptation to open up the smoker and take a peak.