K.C.
We live in Orlando and have season passes for disney, so we are there pretty much every weekend. :) We bought them last December when our oldest was 21 months and I was 6 months preggo. We USE them! I LOVE disney and thankfully my husband does too.
We have taken our oldest to all the theme parks in the area aside from Legoland which opened yesterday. :) It is about 45 minutes away from disney.
Seaworld is alright there are two rollercoasters, one of which is really cool, but in my opinion Seaworld is way to expensive for what it is. We only went there when I was working and we were both free (SW is free for FL teachers) now that I would have to pay we don't go anymore.
Islands of Adventure will have only 2 rides that your 2 year old can do, a carosal and one fish two fish which is the same as Dumbo and the Magic Carpet rides at disney. There really won't be much there for your 5 year old either. The Harry Potter part is okay, but I think they could have done much better. Regular Universal is okay too, but I'm not really a fan. Some stuff is alright, but I don't think there is enough there to fill a day.
Basically we stick with Disney. Staying on property is great, it will save you time and will give you Extra Magic Hours (when only hotel guests can be in the park either early morning or after closing at night.) I would also suggest the meal plan at disney. You can always use extra snacks at the end for things that can be taken home. Like packed snacks. Brin
Plan at least one day at each park. Animal Kingdom closes much earlier than the rest of the parks so that might also be a good day to do Downtown Disney. The TuskerHouse restruant is really good for a sit down place, we love Pizza-Fari for counter service. The pizza is great, hubby loves the antipasta, and even their mac and cheese is yummy. The Lion King show is wonderful and so is Finding Nemo. I think Animal Kingdom might be my favorite park. We really really really dislike the Yak and Yeti restruant though, my advice would be to stay away.
Hollywood studios is a blast as well. My little ones LOVE the disney Jr show. There is also an animation studios (right by disney jr and little mermaid) there are a bunch of characters to meet in there. Mickey Mouse always hangs out in there and then there is an area where you can go in and learn to draw a character, it is different each time. My 2 year old loves it. She gets a lap board and sits on the bench behind us and draws. It is awesome. The Backlot express (restruant right by star tours) has free drink refils. It is one of the only counter servic places in whole park that does so. Lights Motors Action is a can't miss. Fantasmic is fun, but long lines due to limited showing and a bit scary if your littlest scares easy. Like someone else mentioned it is only done on a couple nights a week so check that out beforehand. The second you walk in the park go right to toy story and get a fast pass (or get inline, probably both, because you will want to do it more than once.) The fast passes for that one are usually gone by 10am.
Epcot, is much different than it used to be, there is soooo much to do there now! My little one loves it. There is a Nemo ride that she just goes crazy for. Soarin is great, get a fast pass early they will "sell" out. All the countries are fun. We did the Princess lunch in Norway for my daughters birthday in Feb. It was amazing and worth evey penny. It should be on the dining plan. FANTASTIC! I think there were 6 of the princesses there and it wasn't even peak season. In June you might get lucky with all 10. Mexico and Norway are the only contries with Rides. China and Canada have movies to watch (kind of boring IMO but hubby loves them.) America has a stage show that we often use for downtime (umm naptime) it is cold, dark, and about a half hour long so it's nice to get little one to sleep. I think it's a very intersting show. If you are able to see the singers in the rotunda though do, they are fantastic. The electric umbrella restruant (counterservice) is the other free refil place in the park. It is by innoventions in the main area of the park. There is also a Coke cooldown spot thing I forget what it is called but you can taste coke products from all over the world for free, it's fun. Innoventions is awesome for the kids. I think all of yours will enjoy it. There is so much to do in there. If you are a disney chase visa card holder there is also a spot to do pictrues with characters for a free picture.
and finally Magic Kingdom. Of course my two year olds favorite place. I think her favorite things there would be meeting the princesses (to the right as soon as you walk in the gate, mickey and friends are there too, but she is scared of them) the peter pan ride, and the castle show.
Fantsey land has a new addition opening in Spring 2012 so I can't tell you about that yet, but I know there will be Belle's castle as a dining place. If you want to eat there I would look into reservations asap, it will fill up fast for the first year or two. For dining we love Pacos Bills and Casey's both casual dining.
I know I basically wrote a book, but pm me if you have any other questions that you think I could answer.