Not a guy, but I'll give it a go.
Guys are weird. Plain and simple. And they say that girls are weird.
Anyway, my guess is that the first guy is mean to you because he feels he has to show off for his buddies. He doesn't want to be made fun of. Tell him to get bent and leave you alone, he isn't worth your time.
As for the second guy, if he goes out of his way to make time to talk to you, or does things that your other guy friends don't, I would say that he likes you. Maybe one day you should just come right out and ask him!
Don't stress out wondering if a guy likes you. Chances are, you'll know if he does or not. I really can't explain it, but you'll know.