If you like horses, Finca Valmy tours is great. They will pick you up at your hotel, it's about a 30 minute drive ot so to Valentin's place where you start the ride.

Sorry nina, I didn't see your other questions the first time. As far as the restaurants, we really didn't venture out as much as we had planned on. El Avion (the restaurant in an old cargo plane was horrible). I would go with recommendations from other Fodorites on this site. The Tulemar restaurant isn't great but its not bad either. Breakfast and lunch were actually pretty good. We liked the chicken quesadillas best (NOT the beef!).We ended up eating there a lot because we were either too tired (lazy?) too go out or it wasn't pouring rain. We had room service there one afternoon too. As far as tours, we did the 1/2 day white water rafting but I would recommend the full day instead (unless you are rafting somewhere else on your trip). Also,if you really want to see the wildlife, hire a guide and tour the Manuel Antonio Park. There again, unless you are going to the Osa where you will see a lot more wildlife.
The private beach at Tulemar is great because it is very nice and very few people. Everything you will need is down there--no charge. Bring a good book too because there is plenty of shade once you've had your fill of sun. The only thing that's kind of a pain is that you can't walk to the beach (its pretty far) so everytime you want to go down there you just call the reception desk and they send a car to pick you up and drive you there. We also had to call and for the car everytime we needed to go to the reception area (e.g.for a tour pickup).There is no charge or tipping for the rides and we never waited. Most of the time by the time we walked out to the driveway, they were there. From Mot-Mot you can easily walk to the restaurant and pool.Warning-As you might expect the snacks and drinks in the fridge and bar in the room are very expensive so if possible, bring your own goodies!

You don't need a car, but we had one and appreciated having it. We drove down to the private beach, and could come and go as we pleased. Also made going out to dinner easier, down to the public beaches, and the park. It was very convenient.

Restaurants in MA weren't as great as others we've been to in Costa Rica, but these are some:

Ronny’s Place - good meal...VERY casual, but the best for the sunsets/view, get there early and wait so you get a good table.
Marlin - great fresh fish off the beach, we went for lunch
El Avion - is also good for sunsets, food was OK, I wouldn't say it was terrible though, we didn't regret it nor did we rave about it.
Napoli Pizza - didn't go there but heard decent things about it.
Barba Roja - supposed to be very good, didn’t make it there