I've never understood not wanting to experience new things, I for one can't wait to go to DLR for the first time and of course TDR is on my bucket list. If people are fans of Disney, they should be drooling to experience more of what it has to offer, although stay off my precious DCL, I don't need the prices to go any higher!
You are in for a treat! When do you plan to go? Make the classics a priority over the newer stuff. Trust me. Even though, the names of the rides may be the same, it's a completely better experience (excluding Splash Mountain). Make sure you do:
Indiana Jones
Roger Rabbit's Cartoon Spin
Alice in Wonderland
Pirates of the Caribbean
Big Thunder Mountain
It's a Small World
Space Mountain
Haunted Mansion
Even though Florida's version of the Haunted Mansion has a few additional scenes, I can't explain why, but I like the California version better. I hesitated to put it on my list simply because the Florida version is supposed to be better, but I'll let you be the judge.
EDIT - I forgot to mention Tower of Tower. The DCA version is different than the DHS version. It has better special effects, but it is "darker" in tone and completely lacks the Fifth Dimension scene. Ride it for comparison's sake, but I prefer the Florida version.
EDIT #2 - I added Indiana Jones and Cartoon Spin. Indiana Jones is a super-must-see. Cartoon Spin is worth seeing (but do the classics first). I did not include Pinocchio, Mr. Toad, Canal Boats, Snow White, Columbia Sailing Ship, Winnie the Pooh, or Buzz Light Year because these are not must-see attractions for people who's been to WDW millions of times, in my opinion. See Buzz Light Year, even if I did not include it in my list because the DL version is superior, but still not a must-see. I did not include bobsleds because EE at AK is superior, but see it if you have time because it's a different kind of ride. Of course, see RSR at DCA.