It depends what you want really. The other poster was right - Lago, PArk and Floral are all part of the Garden apprtments complex. It's a Swedish company I think. We stayed at GArden last year and I have to say we loved CB.
All 3 are not too big (Garden has about 60 appartments). Lago is nearest the marina - in fact it actually sits on top of some of the restaurants fronting the marina. All the night life for Garden is based at Lago which has an open air stage built by the pool. Some of the appartments actually overlook this though others are well out of the way.
I would DEFINATELY contact your agent and request a quiet appartment if I were you - unless you prefer otherwise of course!
But I don't want to give you the wrong impression. The appartments seemed OK from what we saw. We had a few problems when we arrived and the staff fixed them straight away and were extremely helpful.
You can use all the facilities in each complex (not much more than a pool really) and I would recommend trying out the other pools.
Cala'n Bosch is a lovely place. The marina is surrounded by restaurants of all types, all essentially outdoor and all welcome families even though some are quite pricey. It really comes alive at night (in a reserved kind of way).
You are yards from shops banks car hire etc.
The beach is quiite small but clean & you can walk along th erocks. There's a bus stop right outside Lago with buses to Cuidadella which is worth a visit. Also I'd recommend the little train ride around the resort - good way of seeing everything.
Any other questions I'd happy to answer (but as always just my personal view!)