yes universal better for older children.
the best parks that we all loved were busch gardens and seaworld. lots to do for everyone. busch gardens has a few big roller coasters such as cheatah hunt but lots of animals for the little ones to look at as well as sesame treet world and we spent two days there. seaworld tickets we brought could be used at seaworld, busch gardens and aquatica, a water park.
seaworld was awseome, my favourite by far, i even went on manta the new rollercoaster where you are lying flat face down and i am not a roller coaster fan.
for us the best parts of disney were the other parks as far less crowded, epcot, test track is brilliant. Animal kingdom was great as well and so was hollywood studios, that has a really good show at the end of the night with mickey and friends on boats and lots of firworks etc, but get there early.
i may be in the minority but i say avoid discovery cove. People go there to swim with dolphins and you get literally a 30 second swim. you do get a long talk beforehand and when in the water in your group of people, i think it was either 6 or 8 people in total in each group, you get to stroke and feed the dolphin, but the actual swim is insanley short. and no freeplay etc. the site is lovely and its free drinks and food all day long, but its not worth the fortune you pay to go. also that was the only day i got burnt, using the suncream they provide.
2 weeks in florida would be the holiday of a lifetime and would be fab to go all out. i thought that would be the case the first time we went and easily spent £15k on travel, accomadation, tickets and food. it does kind of tar other holidays though as florida has so much to do, especially in orlando. i recommend staying off site as well. when you stay in a disney or universal hotel you end uip spending all your time there especially as thier free transport is geared towards taking you to thier parks and nowhere else.
whereas most hotels on international drive have free transfers for universal parks and seaworld parks (even transfer to busch gardens was free and thats over an hour away) but disney transfers not included unless says so specifically. there are plenty of taxis and dont be afraid to get in one of the licensed mini buses that will tout you while stood at the itrolley or bus stops or you can catch a bus. the times we went without a hire car and stayed on international drive i felt we saw a lot more of orlando than when we hired a car.
for shopping the outlet malls either end of international drive are ok, but dont expect nice clean shops, lots of bargains, but a few of the shops are just shops and not outlet ones. the best mall was florida mall and there were bargains there as prices cheaper than the uk. Florida mall had your normal high street type shops whereas milennia mall is the designer mall with tiffany, gucci, etc and not child friendly.