The best style is 80s hip-hop or old school hip-hop. The rap in these days SUCKS! You gotta try listening to artists like Grandmaster Flash, Afrika Bambaataa, Whodini, Planet Patrol, EPMD, Run-DMC, Man Parrish, Lovebug Starski, Kurtis Blow, and more. That is real hip-hop.
I like Sky's the limit by little wayne.. really good beat on that one
some others would be: Lose yourself, rabbit run, dirt off your shoulder, kingdom come, empire state of mind, none shall pass, Tonight (by PNC- some underground group but it's a great song), California love, x gonna give it to ya, party up in here