Quiet as kept, Dre's best beats are all on the D.O.C.'s "No One Can Do it Better" album. Probably the most underrated album of all time, and Dre's best. Real talk.
I don't know about the top 5, but the top 2 are Lyte and Lauren Hill for one reason. They are the only two female MCs in history who in their day were among the best doing it, period.