Oh man, tons!!
Megan is right -- Smyrna is great (each of the beaches are different -- depends on what you want to do and what you're looking for). The Cape is NOT what it used to be -- it's more like a 'Park' now -- you can easily spend all day there -- but it's not 'free' anymore either. But if you are at all a space geek check it out. (I'm with Megan - it's one of my favorite places).
Sea World isn't 'big' - it's no where near as big as Disney nor Universal. They do have a penguin exhibit -- we didn't see it yesterday cos we ran out of time. I like penguins too!
I like Busch too but that's 2 hours away.
Probably my favorite 'recommend' is Silver Springs -- about 1 1/2 hrs n. of Orlando in Ocala. It's where all the old Tarzan movies were filmed *grin*. But the Silver River is gorgeous and you can see the bottom of the springs as clear as glass. Tons of animals -- they have an animal 'kingdom' that has nearly as many animals as Disney's Animal Kingdom but they're more visible and you see none of the repetitive "stress" movements -- these animals are in a pretty darned close to 'natural' habitat. You can take different boat rides (there's a Jungle Cruise, the glass bottom boat and others) -- not tons of wait time AND there is usually a big bird show ("In our opinion there is no such thing as an untrainable animal -- you can train ANY animal with positive methods" -- that was the first place I ever HEARD that!)
They have a concert series -- I *think* Kenny Rogers will be there March 1 -- dunno what your music taste is, but it's free (included in admission - a lot of the parks do that down here - particularly that time of year).
http://www.silversprings.com/
Cypress Gardens is a little more zoomy -- they have rides AND the "gardens". That's just south of Orlando on I-4 (you get off at the Winter Haven exit of I-4, go south on 27 and follow the signs to Cypress Gardens).
I think their Flower Festival is the last week of March:
http://www.cypressgardens.com/
Now again -- if you're really into nature, or gardens, further south of Cypress (continue south on US 27 and follow the signs just before you get to Lake Wales) is Bok Tower Gardens -- Bok Tower is a carrillon -- a bell tower. It plays on the half hour and there's always a concert on Sunday.
I know they have a special play going on the night of March 1 (it's actually a friend of ours -- he has a one-man show "Twilight at Monticello" -- about President Thomas Jefferson -- he's done it all over the country, including at Jefferson's home, Monticello) but I don't know if there are still tickets. But the Gardens itself is gorgeous, squirrels, birds, hummingbirds, and small animals all over the place -- now David and I are prone to just taking a book and disappearing there for a day. Just pleasant -- gorgeous and not something you'll see anywhere else. But NOT "zoomy" -- if you're looking to be entertained that's NOT the place for you.
http://www.boksanctuary.org/
Now right "in" Orlando -- just north of Orlando on I-4 is "Maitland" (tiny little suburb) but it's home to a great predatory bird sanctuary/rehab facility sponsored by the Audubon Society - it is GREAT. Won't take you a long time to go thru it but it's a great place to get lost for an afternoon -- totally at your own pace, and stand and gawk at the birds as long as you want. OR you could be done in an hour -- your choice.
Centers and Sanctuaries (they don't have a website)
Audubon Center for Birds of Prey
1101 Audubon Way
Maitland, FL 32751
407-644-0190
Bird Island,Colclough Pond, Egret Island, Sabal Point, Saddle Creek, St. John's Marsh, Sister Vesta Newcomb, Turkey Creek
c/o Audubon of Florida
1331 Palmetto Ave., Suite 110
Winter Park, FL 32789
407-539-5700
Now if you like water parks -- Sea World is going to have a new one opening NEXT week. Aquatica -- it actually sounds like a lot of fun (and I'm not into water parks but a lot of this sounds great).
Also -- there is Discovery Cove -- less well known but it's where you can go swim with dolphins. They have many different 'packages' -- it IS pricey but it's pretty awesome too.
http://www.discoverycove.com/default2.aspx
Beyond that you can go to the Orlando Sentinel (newspaper) and go down the left column to "Entertainment" -- and there is an automated calendar that will show you ALL there is to do on certain dates. You have to troll thru a lot of wine tastings, etc. but you can pick various types of venues. Fun tho.
http://www.orlandosentinel.com