Yay for two days! One day for a first trip to DLR is like when you hear about someone going to WDW for the first time for two or three days.
You won't be able to see everything, especially in the summer, but I think since you're a WDW vet, you'll be in good shape.
Everyone had really good responses so far, but I can't resist offering up my own list. This is a list for someone who feels they can skip the clones or the inferior versions:
Disneyland
1. Indiana Jones and the Temple of the Forbidden Eye
- You won't believe this is basically the same ride as Dinosaur.
2. Space Mountain
-A smooth, modern coaster with a ride-synchronized soundtrack by Michael Giacchino.
3. Pirates
- So much more to it in CA: more drops, the bayou scene, the better audio, and MORE RIDE.
4. Toontown
-Roger Rabbit is a good dark ride and the whole land is neat. It's the version that woulda coulda shoulda gone to DHS off of Sunset Blvd.
5. Fantasmic!
-When you only had one night, I was going to suggest skipping this, but it really is a lot better than Florida's. It has clearer water projections, a cool Peter Pan scene, and an IMPRESSIVE dragon. I haven't bothered to go to the DHS version in a while, but I love the DL version.
6. Buzz
-This is another one that I don't love in Florida, but am crazy about in California (just look at my username/avatar if you don't believe me!). It is a very similar ride, but it has several smallish touches that really let the ride live up to its potential... makes it a completely different experience for me!
7. Autopia and Pirates Lair at Tom Sawyer Island
-I bunched these together for two reasons: your 7YO will probably really enjoy these even though you wouldn't be going on them if you were on a solo trip, and these attractions would never be built like this today. The piratey additions to the Island are actually worthwhile, and make sure you check out the caves: they're different than the ones in MK and there's actually some tight squeezes! They are anti-ADA. It makes it feel a little more like you're really exploring; there was at least one spot where my 6YO could fit, but I couldn't (I haven't missed any meals, but I'm not a really big guy). The Autopia is SO much more than the four left turns you get on the Tomorrowland Speedway. There's bridges and underpasses, the cars take different routes through a very green area, and the monorail goes right overhead. I don't remember whether it was the monorail track or another part of the Autopia, but there was an overpass over our car that was low enough to easily touch. You'd never build something like that today!
California Adventure Must-Sees
1. Radiator Springs Racers
-It MUST be experienced! Get in line for Fastpasses before the park opens.
2. World of Color
-I recommend getting some counter service food and getting there as soon as the Fastpass return window opens; being right next to the water made it a completely different experience for me. The show towers over you! For a daytime taste, check out Instant Concert-- Just Add Water!
3. Aladdin
-It's easy to skip because there's only so many shows and you may not find yourself in that corner of the park at the right time. I myself spent three weeks' worth of time at DLR before I actually saw this show... now I regret it! Especially since you have two days and especially since your wife likes the Beauty and the Beast show... don't make the same mistake I did!
4. Monsters, Inc.: Mike and Sulley to the Rescue! and Mermaid
-both high quality (though not mind-blowing) dark rides that shouldn't have long lines. Monsters, in particular, holds a special spot in my heart because it is a creative retheme of a disastrous ride called Superstar Limo. Look it up on Youtube after you ride Monsters! Monsters has a lot of "tricks" packed into a little ride: projection mapping, multiple scents, as well as an interactive animatronic.
5. California Screamin'
-Spiritual sibling to Rock 'n' Roller Coaster: a launched steel coaster with an inversion. This one is completely outdoors with a long track and unique layout, though, so it's obviously different. Try the single rider line if your 7YO isn't tall enough.
6. Animation Building
-Even if you don't do any of the activities, it's worth it just to look at the beautiful screens in the lobby filled with backgrounds, concept art, clips and sketches that showcase various animated movies one at a time. Plus, the air conditioning will feel pretty good in July.
7. Cars Land lighting ceremony
-Grab yourself a snack at the Cozy Cone, find a spot on a bench right at sunset and wait for "Shh-Boom" to start.