SuperNewbie:

Brian's advice seems pretty appropriate; finding a local catamaran sailing club would be the best way of choosing between all the different styles of boats. You mentioned a few things, though, that you should be aware of from the start:

You really do have to have some respect for the water and be able to tell present and future weather conditions. As a practice, each morning get up and turn your computer on and see the local marine weather report. Get a feeling for what winds feel like. You'll need to know what kind of weather to expect before you go out.

You also mentioned 4-5 people riding on your catamaran, and this is done very rarely, though you could do it with a larger boat like a Hobie 21 or a Nacra 6.0. However, these boats are very powerful and cumbersome. They're difficult to move around on the beach and they're even more difficult to right if they flip over. There are tools (e.g. Rick White's power righter) that can help, but they take a fair amount of practice and experience on the water.

I think a person can learn to sail on a catamaran, not necessarily a small monohull. Most of my friends in our club did exactly that by coming to a cat owner at the beach. It's really not that difficult; you can probably learn to sail in light winds (around 5 knots) in less than a day. Learning to race will give you the highest learning curve.

One other thing; I can't think of any newer catamarans that now have reefing points on their sails. I think Hobie Cat stopped doing that around 1979.

Have fun.

Wyatt