How old (roughly) are you guys and what kind of amenities are you looking for? If you want absolutely-nothing-going-on pure gorgeousness of beach and tropical jungle amazing, the southern tip of the Nicoya Peninsula in Costa Rica is hard to beat.
Specifically the very small town of Montezuma, which has some amenities and was founded by ex-pats and the virtually non-existent towns of Mal Pais and Santa Theresa which have surfers, and a laundromat/internet cafe run by two israeli guys who make
amazing food.
Montezuma:
Mal Pais: