If we're talking greatness: Russell, Bird, Cousy, and Havlicek are easy. After that you're picking between Cowens, McHale, Pierce, and Sam Jones. Hard to go wrong with one of them. Hell, it might be more fun to pick the B-Team.
Let's go with that list and put Sam Jones on the team. That leaves the second roster with Cowens, McHale, Pierce, Jo Jo White, and Dennis Johnson (all HoFer's).