There is a vast amount of ragga/reggae to choose from depending on what sort of era you want to go with.
Some good old tracks that go down well are:
Buju Banton- Walk like a champion or girl flex (never play boom bye bye though)
Shabba Ranks- Mr Loverman, Trailer load of girls, Wicked in Bed
Supercat- Ghetto red hot, My girl Josephine, Don Dada
Mr Vegas- Heads High
Also have a listen to Capleton,Cocoa Tea, Sizzla, Beenie man.
If they want some reggae as well i would definetly play a couple of beres hammond tracks,The two i play are : Tempted To Touch and Who