I agree...
You can do it as 'cheap' or as 'dear' as you want...some people think that it costs thousands and thousands (and i mean thousands!) to go to disney...it really doesn't..it can do mind

!!!
It is like a mind field if you've never been...bella has given you a good outline of Q's you need to answer before you can really determine cost...
To give you an idea (sorry if you already know this

) but disneys situated over hundreds of acres...disney as a whole includes Magic Kingdom (with cinderellas castle), Animal Kingdom, Hollywood Studios (formally MGM studios), Epcot, two water parks - typhoon lagoon and blizzard beach and an area called downtown disney with restaurants, shops and a really good all round atmosphere for people of all ages...
Universal is similar to a film studio with many of the rides based on movies such as The Mummy, Jaws, Twister, MIB and the newly created ride The Simpson. Islands of adventure is more of a theme park with rides again based on tv programmes such as Spiderman, Hulk, Jurassic Park.
Both Universal and IOA are based next to each other.
Seaworld you may've heard of....very nice park in my opinion...animal shows, rides etc...great for all ages.
Busch Gardens...i've never been but you do need to get a bus there and it takes a good few hours i'm told as its on th west coast of florida...
Hope this helps....you know where we are if you want anymore help...i'm sure i've forgot something but oh well....
and welcome...