What fish are for me?

So I'm in my new house, and I would love to have another fish tank, but the big question is where do I put it? and what kind to get?

Here are the issues:
1. Really no place to put it since we don't have our living room set up yet, and my computer room is too packed as is.
2. I have young kids. "But what do kids have to do with fish?" "They try to feed them which is bad"
3. Money (of course)
4. What kind, fresh or salt

The advantage really goes to fresh simply because they are much easier, and less expensive in the short and long run. But I'd love to get 100+ gallon tank, and they cost a pretty penny to buy and set up.

So for now I'll just have to get a new screen saver, but I might have a few items on fish tanks in the future.