there are about 3 different threads in this forum that has most of the questions and answers you have asked about. quite a few of us have posted on those.
i am not trying to pass off your question, not at all. its just i have repeated myself in them so many times, i think people reading them are getting tired of me.
yes, you can do both parks easily.
the key is to start early.
be at the line around 8:20 when the park opens at 9. there are times they open universal early and you will get a head start.
some people post to start at ioa, while others say uo.
the thrill rides are here, more so than disney imho.
there is a thread about where younger kids can have the most enjoyment as they would not meet the height requirement on the big coasters.
i believe phamton posted the sites and listed them. one other poster did also.
you can go as a family to the thrill rides, yes universal wins this hands down over disney, and do the child swap. the 2 year old would not be able to do hulk, dueling dragons, ie. one adult rides with the 8 year old, they get off then the other adult rides while adult #1 stays with the 2 year old.
this way you don't have to get back into the line and wait again.
i have done both parks in one day but i do the highlights of the rides and attractions i have to see/do. the only way to accomplish this is to go early, eat your lunch at an off time. try to aim for 11:15 when no one else is there, do an early dinner or later dinner. you may have to do a snack for the kids if you eat late thought.
go opposite of the crowds. see that thread for advice.
i would not buy my tickets at the gate. the only discounts there would be the fan club card,
AAA or mc and they discounts aren't as great.
if you buy the special pass for $99 that is going on now on line, you can buy a 5 day pass adult and get one child ticket free.
so for $200, you get 4 passes good for 5 consecutive days for he entire family.
a one day pass for 2 parks is up there at $77.75 per person.
you can not hop from one park to another with out the 2 park option.
so, if you buy a 1 day ticket for all of you, 2 adults, 1 child 8 yr (child 2 free) it would be over $200 right there. 77.75+77.75+ 67.10 =$222.60
tax is included on those figures.
since you are going to be in florida for 8 days, spend more than one day at the parks.
buy the passes on line and save over $22. if you only use 2 days of those passes you will still come out way ahead.
now if you buy only a one day park ticket and want to upgrade it when you leave to a 2 day park ticket, you go to guest services and pay the increase.
it is cheaper to go that route than to buy another ticket if you decide to come back in a few days.
the 2 day, 2 park tickets are $114.97 per adult and $104.36 for children
if you went that route at the gate you would be paying $332.30 for 3 people to go 2 days to the park.
that $99 5 day 2 park pass sounds pretty good now, eh.......
by the way, i think it is 104.xx w/tax for those bonus passes.
the bonus passes can not be bought at the gate, only at the online univ store