I think the Ritz is your best bet IN Georgetown. But, if that's too $$$, try the Westin Grand on M and 23rd-ish. It's just a few blocks farther than the FS from central GTown, and very nice (and very moderately priced).
I strongly advise AGAINST the Marriott Key Bridge. It's perhaps one of the most poorly maintained and poorly run Marriotts I've ever seen.