What do you recommend for an air drill?

[71CHEVYSHORTBED402]

Beginner here. I've never owned one & don't really know what to look for. My compressor is 13 ga. 5.5 @ 90 PSI. At any rate, I'm hoping to accomplish:

1. Low speed for buffing out our original plastic steering wheels, with white rouge and a buffer similar this http://www.eastwood.com/canton-flannel-buff-wheel.html

2. Long story not short enough, I'm removing the useless aux. tank from my driver. Two of 10 #10 screws wouldn't budge off the cover attached to the bed, so I had to cut off the heads. Either the moderate electric drill won't cut it or it's the Irwin cobalt bits I just picked up, and I'm guessing it's the drill. Anyway, I can't seem to drill out what's left of the screws. Should be easier. High speed better?

3. I don't know, maybe some type of pads on arbors to clean-up up the frame prior to paint. That and all around DIY use.

Thank you.