I'm biased, I own a timeshare on I-Drive. But I think one of the timeshares would suit you. We prefer a TS condo to save money - eating in a restaurant costs a fortune for a family of 5 (DS6, DD8, DD11).
Here's the link:
http://www.bluegreenonline.com/explore/resortDetail.aspx?ResortID=14
This pool just opened in March 2008. DW and I just took a week at the MGM Grand in Las Vegas, which has a great pool - but the one above is definitely better. We've tried a couple other Orlando TSs but we like this one best.
There is a Sheraton across the street which also looks like it has a good pool, and I'd love to try the Hilton Grand Vacations down the street, it looks great.
There is a publix grocery store near there, and a wal-mart superstore a little further. The south end of I-Drive is about 10-15 minute drive from either USF or Disney, less than 5 min from SeaWorld/Aquatica.
I'm not suggesting to buy one, and be VERY careful if you "volunteer" for any sales pitch, they're usually high pressure. That's how we ended up with ours here, but we don't regret it in the slightest (just don't buy too much, start with 1 week every 2 years if you do, and pay close attention to maintenance fees which are the dominant expense IMHO).
You're better off renting weeks or points. You'll probably pay more than for a vacation house rental, but you'll get a really big, really cool pool area which you wouldn't at the house.
I have gotten a week at the Sheraton for $300/wk or $350/wk a couple of times through RCI, which had a large multi-pool area but not as nice as the above, IMHO. I've seen the Fountains for around $420/wk last year. (All were 2BR sleep 6, incl dishwasher, washer & dryer if you need 'em)
You can rent DVC points, but I think these would be more $$$ than offsite, not worth it IMHO. But you'd definitely get a great pool, access to Disney busses incl. ME, and still have multiple rooms and a kitchen. If you use ME and decline a rental car, you'll have to figure out how to get groceries.
We always get a car (I hate waiting for busses anyway), head down to a grocery store and buy a shopping cart full of frozen food (pizzas, chickenburgers, etc.). It's cheaper than a restaurant and easy to cook (one parent heads to the pool with the kids, the other fires up the oven and takes a break). We try to eat a little healthy with pre-made salad kits, but we admit if we were in a restaurant the kids would be eating chicken nuggets and french fries anyway.
