Should be fine, generally you want to go for the highest mAh battery that will fit in your gun as this will give you the most shots out of a charge. There are a couple of commonly recommended chargers - One is the Turnigy Accucel 6, which I believe is a clone of another charger which I can't remember the name of.
Personally I use 7.4 1350mAh batteries, I find one lasts me a full day but I like to swap them out at lunch just to be on the safe side. Plus as I have 3 of them it seems silly to run the risk of damaging a battery by running it down too much.