You dont need an impact wrench to remove the lug nuts, just a good breaker bar. The impact is quicker and easier however. A torque wrench *should* be used for final tightening after you put them back on but you can just use the same ol breaker bar and just make sure to put some oomf into em as you tighten them backdown. Dont forget to tighten in a star pattern.
(you can rent torque wrenches from local auto parts places but for one that makes 90lb/ft it might not be cheap)
pads wise, just use the factory replacements. If you're not modded there's no sense in going nuts with brake parts. The factory spec stuff is pretty decent. Getting them from the dealer wont be cheap but they'll be exactly what the car came with. Going to autozoo or the like will get you oem quality stuff (after market mfr's have to maintain same as oem standard or exceed it by federal law) a little cheaper but may not be exactly the same composition of friction material (might make more or less dust...but will stop just as well).
Personally I hate working in the cold.. but if you can get some way to keep your hands toasty (dexterity will help the job go quicker) thats all the better. I'm sure with all the recent snow working on the ground is going to suck.. if you can get the car into a garage thats favorable but if not, see if you can score some cardboard or old carpet to sit on while working on the car. Sitting on cold/wet ground gets old fast even if its a short job.
You'll also need a floor jack and jackstand (stands come in pairs.. but generally are not very expensive) Make sure you properly and securely support the car. A long handled 3/8" drive wratchet too.. I highly recommend the long handle. Leverage is your friend.. especially if the caliper bolts are pesky. Penetrating oil.. pb blaster or liquid wrench. both work really well and should be applied to any/all rusty bolts prior to loosening. Let it chill for a little while before you have at it. This keeps the possibility of breaking a bolt to a minimum.
You may want to snag up a Allen head set (3mm-8mm or so) for your wratchet.. as well as a set of torx bits. (if you dont use either set durin the job I'm 100% sure you will use them at some point.) These are all available at autozone or sears.
While at the auto parts store, along with one can of penetrating oil also get two or three cans of brake cleaner. I prefer the cheapy autozone generic stuff. You'll want to hose down the brakes to get the gunk off before you start in.. as well as hosing off the new rotors to get any coating or oils off of them.
as much as I hate to feed the retail monster, the antiseize packets they try to sell you along with the pads are actually usefull. smear it on the back (NON friction side) of the pads on isntall and it stops them from squealing. That stuff is also good to use to lube the caliper bolt threads and any sliding/moving parts.
Once you finish this job and get back to us you'll be a new man .. I'm tellin ya, once you're finished and it works you'll have much more confidence working on your own ride. We've all literally been in that spot, unsure... uneducated.. that first step and the courage to take it are the most important.
Oh! side note.. I do this with drum brakes because they're like puzzles.. shoot pics as you go a long, especially if you're unsure how something might go back together (usually not a problem with disk brakes but it can be helpful) .. and do one side at a time. Not only that but if you need help you can upload the pics and we can better see what step you're at.