Yep, check the plugs, points, distributor cap, etc., etc. - all things related to ignition. If the plugs are questionable, pop in some new ones. They're only $2.00 each.

The contacts in the TPS can be cleaned with alcohol and some people use an ink eraser to clean them. The ink eraser is just barely abrasive enough to clean the printed contacts without completely tearing them up. The trigger points can be lightly filed or cleaned up with fine sand paper just like you would do with the ignition points. I've found the easiest way to check the trigger points is to pull the distributor out of the car. If you only remove the bolt that holds it into the engine, and don't loosen the pinch bolt above it, you won't lose your timing. Once the distributor is on the bench, it's much easier to connect an ohm meter to the contacts and spin the shaft in order to see approximately how many degrees of dwell each of the contacts has. If you find that the trigger points are barely breaking for just a few degrees of rotation, you can pull them out of the distributor and tweak the stationary side of the points to give you more gap (or more degrees of "open").