I went there in January of 2007 with DH, and the 3 kids. We had a great time but it can be overwhelming to plan.
I can offer some suggestions of what we loved / didn't care for but the best advice I got is to go expecting to spend obscene amounts of money on food / drink / entertainment and we did - for the 5 of us (the 3 kids always just had a children's meal) we spent about $1500 on lunch / dinner w/o drinks. Breakfast was included in our trip (we earned it as a sales incentive) so lunch was light pool food most days and then dinner varied from Carmine's (we loved it) and the expensive steak place (a little stuffy for us) to the deli and Johnny rocket's.
I;m assuming that it's just you ahd DH since it's a 20th anniversary trip so a lot of what we did won't apply but if you have any questions, I'd be happy to answer them.
Happy planning