Ok, if you want to do a full tune-up, here is what I do (I'm giving the checklist I use when I buy a newly used vehicle, I use the same list for a regular tune-up, just minus out the things that may already be taken care of like oil change).
1) New plugs. Like I said, I go with OE or performance, whatever is nicer to my wallet at the time.
2) Plug wires. OE or performance, whatever has the better price but I usually lean towards performance because quality electrical wire is important.
3) Cap and rotor for ignitions with a distributor. I go for the brass terminals if I can afford it. The cheap aluminum ones can be a nightmare.
4) PCV valve. I usually do them when I get a vehicle because it's an often neglected part that is cheap to replace. Every 50k after that it gets done. Been doing that since I had a truck that kept spitting oil out the exhaust and I couldn't find the reason. Replaced that valve and it fixed the problem.
5) Oil change. Nothing but Motorcraft filters. (hint, walmart has a decent price on 'em). Change the filter an use a decent grade of oil. I'll add about a cup of ATF (1/4 quart) to the oil too the first time or two - old mechanics trick for cleaning some of the gunk out without really harming any gaskets.
6) Air filter. You wouldn't believe some of the ugly air filters I've seen. I swear some people never pop the hood to check things till the check engine light comes on.
7) Fuel filter. I try to change them every bout 20k miles. I've been told by a number of people that only one bad tank of gas can gum up a filter.
8) Check the fluid in the transmission, transfer case (if 4x4), and axles. If it's low but the fluid looks good, I'll add some unless it has an obvious leak. Otherwise it gets drained and refreshed.
9) If it has an automatic transmission, it gets both new fluid and a new filter. Autos like clean fluid and filters - they last longer that way.
10) I've been forced to add this one lately because of electrical problems. Check the alternator, battery, all the wiring (just a visual check on the wiring for problems), feel the ground wire off the battery, flex it and listen to see if it sounds crunchy, replace if it does. Check the fuses and relays to make sure they all look good (I had a truck with a fuel problem and found that somehow the relay got smashed, somebody wrapped it in cardboard and electrical tape - I kid you not). I'll check the coil and TFI module too if applicable. My F-150 had a weak coil and a TFI that fails one of 6 tests which caused hard starting and some stumbling. Autozone stores can test the TFI and coil, not sure about any other auto parts stores.