I'd recommend the Al Bustan Rotana hotel. It's right opposite the airport. The Le Meridien Dubai is next door and is very good alternative. Most hotels in Dubai allow early check-in, so you should be able to get a room before the normal 3pm check in.

There are a number of restaurants in and around the hotels. I think Sukothai is fantastic, and pretty reasonably priced.

I've not done the Sundowner safari, but we used Arabian Adventures for a desert safari, and they were pretty good. They took us for a ride on a camel, and then out into the desert.

Cheers,
Rick