How many K's are on the car? There is a spec for when the timing belt should be replaced, it's there for a reason, do it then, not before and not after.
Maintenance is key, there's no point in spending all this money on aftermarket parts and then never changing the oil on the car, or brakes and so on.
Just buy the regular recommended spark plugs for your car, search Unabombers manifesto, there is a thread in there to do with the plugs that are supposed to be used in our cars. Don't waste your time or money with "high performance plugs"