I think if you really wanted a "best starting lineup" you would need to take roles into consideration, as 9SA21SPURS20 did above. It's actually a bit tough to put together a good team without knowing what chemistry you'd create, although the five best at each position probably wouldn't have a problem against other normal starting lineups. Still, I'm going to go with the best at each position: C - Wilt Chamberlain. The guy had amazing moves, agility, and size. Although he was a ballhog, he lacked a good supporting cast and had to be to go-to guy in every game. Honorable mention: Kareem Abdul-Jabbar - could very well be flip-flopped, and had a longer career with more championships. The reason Kareem loses out is based on my feeling that Chamberlain would have been as successful championship-wise if he had more help. Bill Russell also deserves mention for his incredible defensive skills and selflessness, with incredible rebounding and even more incredible career averages for assists at the C position. PF - Tim Duncan. Fundamentally sound on offense one of the best post defenders in the game, he's led the Spurs to a high seed every year and would make any team an instant favorite. Honorable mention: Kevin Garnett, whose versatility could put him at other positions. Tough rebounder, shot blocker and incredible post player who can handle the ball, pass, and create. SF - Larry Bird. Legendary shooter who never took a day off, and hustled on both ends. Underrated passer and rebounder who was the core of his team. Honorable mention: Elgin Baylor, who had an incredible all around game - great scorer, rebounder and passer despite being undersized. SG - Michael Jordan. Most of the points mentioned above - pure competitor with numerous MVPs/final MVPs/championships. Developed from a slasher into a shooter and consistently played well with his teammates, making his entire team better. Honorable mention: Oscar Robertson, whose incredible 14 year career saw him average a triple double and run through defenses with his offensive prowess. PG - Magic Johnson. His impact could have been greater if not for HIV, the man had impressive court vision and knew how to distribute the rock. He could play any position and wreaked havoc on defenses. Honorable mention: Jason Kidd, a big, fast, and physical point guard with a knack for passing and rebounding, despite not yet winning a championship, there's no question he's improved the teams that he's been on.
Center - "The Dream" Hakeem Olujawon : No player his size has since combined tenacious defense and his sweet offense into one 'flavor' like he did. He could beat you in so many ways. The greatest center since Wilt IMO. Power Forward - Charles Barkley : The round mound of rebound. No one can ever question his talent or his desire to be the best. No one better to have on your side to bang heads with the big boys. Small Forward - Scottie Pippen : Tenacious D and a very very underrated offense. He can play 3 positions,bring the ball up the floor and play unnerving defense on the 1 - 4. Shooting Guard - Michael Jordan : 'Nuf said. Point Guard - John Stockton : I never liked him but he was the best pure point guard ever. Distribute the ball with perfection,step up on O when needed and draw some timely charges. The ultimate floor general. Bench - Larry Bird - Instant offense,tenacity and leadership off the bench. Dominique Wilkins - Instant,earth shattering offense. Dennis Rodman - Tha lockdown. I know some people will take issue with that I have here,but it's the type of team I prefer made up of people I got to see night in and night out. And about the bench,just because I have them on the pine doesn't mean they are less than the starters. IMO You need to keep some of your best players back to insert into the game fresh down the stretch.