Fuel...I'd use Byron's, Maxy's or Mugen Seiki. They all use high quality oils and lubricants without alot of junk to gum up an engine. From all my reading and research these are my top picks.
Are you trying for 1/8 ot 1/10 scale? For 1/10 look at team Magic G4S, Mugen Seiki MTX-4, Serpent 720, Kyosho V-One RRR. Those are the top 1/10 cars available IMO.
Bodies are more personal taste. What do you like your car to look like. Most every body from HPI, Proline etc will perform similarly. It's just what styles you want.
Browse around here...I picked up a ton of info in just a few minutes of reading some of the threads.