JustOne
Ryder Cup Winner
Initial thoughts are that you'll struggle to find a convertible that will hold all the stuff needed for you and the Mrs plus kids of that age. I'm off in a months time and am hiring a SUV, boring but practical.
As for villas then I'm staying at http://www.ihg.com/holidayinnclubvacations/hotels/us/en/kissimmee/discv/hoteldetail stayed there before and everything you need really. Golf courses on siteand near to all the parks. We stayed in a 2 bedroom villa and it was excellent, very large and I got one next to the 5th green on the Legends golf course. Also there's a massive pool and big supermarket on site so you can just chill out for a day or two in the resort if you want.
As for the parks then Disney of course, probably worth at least a couple of days there. I really enjoyed Sea World and Epcot was great. Also Discovery Cove is great for some parental R&R.
Stoopid question but how much does your holiday there cost in total with flights and all..... need to book something for next year or the wife is gonna leave me....