if you are staying on site at universal, then definitely go to disney first.
you will be so spoiled by universal so save the best for last.
when are you planning to go to orlando?
depending on when you go will determine the crowds. stay on site and use the fotl. you will be able to see most of everything in a 3 day stay. when you check out, your room key for fotl is good until midnight on your check out day for the parks.
3 days might be a tough one for a first stay at universal.
rides can be done quickly and you will not have long waits in lines with the fotl card. the attractions will cut into your time at the parks and there are some that are a do not miss. the gory make up show is one of them.
terminator 2 is another big hit.
rides like men in black can not be done only once. with the fotl, you can do multiple rides and kill at least half an hour doing so.
spiderman another biggie as well as mummy. these two rides need at least one repeat to catch it all. if you do the express/fotl for spidey, you do miss out on a lot of the ambience and story line on the way to the ride. you might want to suffer thru with the line to catch it all for spiderman though.
the water rides are soooooo kewl at ioa. again, can't imagine going only once on jurassic water ride.
then you have city walk to roam through. your children might enjoy some of the unique shops. many places to eat and check out.
don't forget the pool at the hotel........you could spend hours at them, especially at hrh where the music is piped in underground.....
we have done universal 15 times. the first two visits were mostly disney and 2 days at universal. this was when only the studios was opened and city walk was limited. in 1993, we split our stay between disney and universal. the longest we have stayed on site at universal has been 5 days.
that gave us plenty of time to lounge around the pool, do the movie and deal (free coupon in the entertainment book for the movie and food at city walk), shop at the sports memorablilia stores at city walk, do both parks, rides and attractions, sit down and dine at finnegans, mythos, lombards and not have to rush............
ok, now what was your question, i get carried away when i talk about universal...........if you are staying on site, 3 days could do it justice.
you won't have the time to hang around the pool for an afternoon or take in all the shops at city walk. if you concentrate just on the 2 parks, it could be done in three days.
any more questions.??