Spike,
Don't run a chemical flush in the cooling system...I've had nothing but cooling problems since I've done that. Just drain and refill the cooling system. If you like, just run distilled water for an hour or so and then drain and refill with the cooland mix.
Fuel? Run a good cleaner like RedLine Si-1. If you feel the need to run a water displacer, make sure you only get the isopropyl based ones, the methyl ones break down over time.
Oil? I'd say run an oil with a high detergent content (even something like Shell Rotella) for a short stint, then change out again to whatever you plan on running. I've had good luck with Shaeffer's Neutra as an engine flush, but I sure don't keep it in there long. This also doubles as a top cylinder lubricant. Certainly, stay away from standard engine "flush" treatments, if you look at the contents, they're often just good old kerosene.
Something I do when I get a car is also flush out the brake fluid. It should be changed every once in a while and I'll bet yours is black as the sith.
For plugs and wires...hmm. I just run NGK and OEM wires. Make sure to replace the cap and rotor as well.
How is your battery? I replace the batteries after about six years or so. If it's original you might want to consider that as well.
Bogatyr