A Group 24 starting battery should be fine to turn over the 4.3. If I were to install a house battery, it would be a Deep Cycle battery. The bigger the better. If you're connected to shore power when you're away from teh boat, then I would opt for an AGM. A Group 31 would make a good sized house battery.
It really depends on how long you intend on being disconnected such as at anchor or on a mooring. Even then it really depends on how many amps you plan on burning. Will you be running the stereo all day, or just keeping the fridge cold?