Unless you've got some power adder(s), like nitrous oxide or a turbocharger, I don't think you'll see any improvements by changing spark plugs. I tried Bosch Platinum +4s a couple years ago and I noticed a decrease in performance and fuel economy. Now I only use the stock NGK copper plugs.

As for plug wires, if your current set is worn out, then replace them. I've heard good things about the NGK wires, but you really can't go wrong sticking with OEM. If your current set is not worn out, then you won't see any improvements switching to "performance" plug wires.