Have you ever played fantasy football? It is where you act like a manager of a football team and compete against other people.
I have.  I actually have played for a couple of seasons.  I normally use ESPN for my fantasy leagues
Cool, the players choose rosters during a draft at the beginning of the season where all NFL players are chosen.
Yes.  There are many types of drafts.  There are auto pick drafts, snake drafts, and auction drafts
Interesting, points are based on the actual games played every week in the real world.
Do you play for money or just for bragging rights?
I play against my coworkers for bragging rights. Last time I played I did pretty good.
How do you determine who to draft?
I watched a lot of SportsCenter to come up with power rankings and then compared my selection to online sites.
Are there playoffs in the leagues you play in?