Hi Mick welcome to the DIS. For a start forget about fitting everything in 2 weeks, it can't be done. What you can do though is cherry pick the that are most important for your family and leave the rest for following visits.
There is a limo service that advertises on this site, and although I haven't used them myself they seem to get good reviews.
Getting Simon's book is a good start as it will give you a better idea of the multitude of things to do. Disney itself is a week minimum. You'll need a day each in AK, Epcot and MGM studios and probably 2 days in Magic Kingdom, adding a day each at the excellent waterparks there's 7 days. Depending on your kids ages You can consider a day each in Universal, IOA, Seaworld and Busch Gardens. Allowing for your day's travelling and a bit of shopping I reckon that's your 2 weeks pretty much dealt with. There are ways of maximising your time, if your kids are of an age where they would like to get autographs from and interact with the characters a "Character meal" or two is the best way to cover a lot of the characters while "wasting" the least amount of time in queues. The meals are a little more expensive than a regular meal, but as the characters come round to your table I'd guess they save you about 3 hours standing in queues waiting for photo shoots and autographs.
Having an itinerary plan may sound like an "anorrak"type thing to do, but on your first trip it really is a good idea to have a loose plan to work from.I don't think I've ever stuck to a plan, but it does allow you to at least have a good idea of what you want to do and it should mean you don't get to the end of the holiday and find you have one day left and 3 days of park tickets in your hand that are "use em or lose em" that trip. I find that if , for example, you find that a waterpark day is forcast storms, bring forward somewhere like SW, Epcot or shopping where rain isn't too much of a inconvenience for the day. Alternatively you may find you planned 3 days in themeparks in a row and you're too tired for the third, swap in a waterpark and move the themepark back.
If you tell us the make up of your group ( number, sex and ages of kids etc) may help to fine tune what are likely to be the highlights for your family.
Things I haven't put in,but are worth thinking of depending on your own interests, are Cirque du soleil, Disney Quest, Space Centre, wildlife/airboat rides, golf, horseriding and a multitude of other activities.