Jan- Feb are execellent months for going to Cuba if you are looking for wind, there is wind almost alll year, July and August are the worse from the wind point of view unless there is a tropical storm coming. So dont go in July or August, yes the weather is very very hot 34 - 38 C and the beach is flat and smooth like butter, but stadistically speaking the wind sucks in July - Aug.
Again, Jan or Feb will be a good time to go, but you need to know that is the winter in Cuba and the cold fronts hit the island twice or 3 times a month, 22 to 18 C degrees the lowest temp average, the good thig is that they last 2 or 3 days with strong winds from the north (onshore) , then it changes to north-east (sideshore). there is plenty of things to do in town (varadero) that are family orientated, and is very easy to get out of the hotel. (varadero is only 24 km long and the beach as well), it doesn take more than 15 min to from the begining to the end.
hotels are many, most of them are right on the beach, there are a couple of them 100m away from the ocean, thats the farthest. Solymar Barcelo, is a good one with plenty of kids, daycare, play yards etc. Playa Alameda hotel, Typ Peninsula (exellent kite beach there).
As i said before, you wil be on the beach, you wont need to move unless the wind changes from east-south east or south, then depending on your hotel you can move to “la punta” (end of the peninsula) where the wind there will be sideshore and very strong.
i hope this help a bit, if you need more info let me know ( you can check the wind with windguru, works great)