tune up questions

alright, i've had my car for almost 3,000 miles. it has 82,000 on it right now. what things should i do to tune this thing up the best i can?

it had the spark plugs changed in june. when i change the oil soon, i'm thinking of switching to mobil1 oil.

the diff. fluid was changed when they installed 3.73 gears, but i dont know when that was.

i changed the fuel filter today.

i'm gonna get a filter recharge kit for my MAC cai.

should i change my tranny fluid too? what fluid should i use?

i'm needing to replace my rear rotors too, one of them is shot, so i'm gonna replace them all soon and replace the brake pads too. should i flush out the brake fluid and change it? if so what to?
 
always flush the brake fluid with any kind of brake work, i use Valvoline synpower DOT 3/4 ATF. it has over a 500 degree boiling point, and is fairly inexpensive. adding speed bleeders is always a good idea.

for fluids, i use Mobil 1 75w90 in my diff, Mobil 1 ATF in my 5 speed and my power sterring, and Mobil 1 5w30 in my motor. changing the fuel filter is a very good idea.