1) it usually depends on how good you are + how big you are.. im 5'9 and skate a 8" board.
2) go to local shop and see what they have. at my shop we have like no name kinda for 20$, shake junt for 16$, redz for 18$...
3) id go for Jessup if i were you. but seriously, grip is not the most important thing. itll get fucked up so quickly that ull have to change it before its over used any ways.
4) 52 are cheap and good. A lot of shops have their own wheels which is what i use cuz theyre cheap. i used to skate elements.
A bit part of skateboarding is personal preference. The more you skate, the more you'll realize what "feel" you like youre board to have.. Start off with stuff thats in your price range, and once u have a bit more cash u can start changing things one at a time and try out new things. try your buddys boards and see what you like. took me a few years to find my favorite set up.