Yahoo! How exciting!
Be prepared for it to be a bit nippy compared to FL, so bring a sweater, lol. Or better yet, forget it and buy yourself a sweatshirt there.
Where are you staying? Will you be there over a weekend?
Arriving early at the parks should be a breeze since you'll be on FL time. You can very easily go from Disneyland to California Adventure and back again, so no need to plan one day here, one day there. DTD is much smaller then the one at WDW, and it's right there with the two parks and 3 hotels.
DLR is built off a busy freeway and busy surface streets. The 'resort' atmosphere WDW has is not the same at DL. You certainly do not notice it in the park, but be prepared that you are in the middle of a city with motels, hotels, traffic, restaurants, etc.