I would highly recommend the Bohemian. Best location of the three and the Bohemian hotels are stunning and fantastic. Marriott is a bit up the river and the Forsyth - while certainly worth a visit for the art and the great bar upstairs - is at the very edge of the historic district.

Skip the traps such as Paula Deens while you're there and be sure to eat at The Pink House - I prefer the tavern area under the restaurant over the formal dining areas.