where in the DR would be suitable for u really depends on the type of holiday you want
Punta Cana, Bayahibe, La Romana ...are more of a resort based holiday as not alot to do off resorts apart from organised tours but these are easy to book , All resort are very large to huge with there own choice of a la cartes and entertainment/ nightlife,Kids Club and kids entertainment everybody has there own favourite resort but i stayed at Gran Bahia Principe Resort and it was great. so goo we are returning this year on31st dec for 2 weeks
Puerto Plata...is the place you can find lots to do off resort many places to visit and it can be done either on an organised tour or off your own back, many areas to stay, Cabarete, Playa Dorada, Sousa, Samana and depending on the area would depend on your choice of hotels Cabarete is meant to be the place where u can just wonder round town, chill at a bar on the beach and has the better nightlife ,,,not stayed there yet but going in June ....Playa Dorada is a gated complex (so very safe) of about 8 hotels with a plaza that has shops/ bars etc i have stayed at a few hotels in the north think the best was The Gran Ventana at Playa Dorada or the Iberostar at Costa Dorada ....
May i suggest that you look into which area u would like to stay then post a specific question bout hotels and there facilities (make it as detailed as possible) on the areas specific forum