Buy yourself a new set of NGK stock platinum plugs for your se-r they perform the best. As far as the rest goes cap.rotor,wires & fuel filter stick with stock nissan parts! You may wanna hit up SE-R.NET there's alot of usefull information on that site to help keep your se-r running strong and living long...
Also clean the throttle body, and reground the MAF. These will help to. In addition, when I did a tune-up this summer, I reset my timing, and it NEEDED it. It was at 11 degrees BTDC; I reset it at 16 degrees (stock spec is 15 degrees). Doing these things made a world of difference if throttle response, and just sheer power. My car is now FAR stronger in the 5500rpm-7000rpm area, and a lot more flexible down low too.
I just bought NGK Platinum plugs, wires and O2 sensor from www.sparkplugs.com The plugs weren't cheap $11 each, but the wires were only $51 and the O2 only $23, so I figure I got the plugs for free considering what I saved on the sensor and wires over what the parts stores wanted for those two things.
If you decide to clean your throttle body, do not spray cleaner into it, then wipe it out. Pull the throttle body off. Some people will say the spray and wipe worked for them and that all the junk will blow out through your exhaust... not true. You would run the risk of that black crap getting on your pistons and else where, w/o any way of getting it out. That stuff turns into a super hard expoxy like subtance when it gets into your engine.