Now my two cents! I'm from Southern CA as well and grew up going to Disneyland...however my DD is 5 and in January we took her to Disneyworld. IMO, World is MUCH nicer than Land. You can do LA in 3 days (taking your time) and still see everything. FL, I would stay a week+ if you want to go see all 4 parks. But, like someone said, there are pros and cons to both.
Land Pros:
Smaller, MUCH smaller for easier navigating.
Cheaper, especially if you stay off site in any of the surrounding cities.
Can't beat the weather, IF you go now. If you wait until August, it will be crowded AND HOT.
Land Cons:
Smaller, with only two parks.
Older, it's really showing its age.
Crowd, more locals and "unsavory" types, as well as schools are letting out now and depending when you go, you might have to compete with the Grad Nights (earlier closings and more traffic)
LA Traffic, it's a mess, ALWAYS.
World Pros:
Much more bang for your buck.
Newer (ie, nicer)
More variety in terms of attractions for all ages.
Much more "Disney Magic" happening. It's really like its own world there.
Free transportation if you stay on-site.
Dining Plan, Dining Plan, Dining Plan (not sure if it's offered at Land, but it's WONDERFUL and SOOOO worth the money)
No crowds in the off-season and weather is PERFECT.
Can be made all-inclusive
Rides offer assortment to young & old.
World Cons:
More expensive, but not as much as you would think. We stayed on site, in a mod resort, for 5 nights and 6 days, deluxe dining plan, with RT airfare for three (non-stop!) for less than $3K. We paid in advance and didn't have to spend a dime when we got there (well except to tip for the sitdown meals and souvenirs.)
FL is HUMID. Even in January. If you want to sweat to death, go in Summer. :)
Much more spread out (ie, lots of walking). DW is HUGE.
In my opinion, you can go to Disneyland first and be impressed. But if you go to Disney World and THEN go to Disneyland, you will be disappointed. It's SOO different. Don't get me wrong, I LOVE Disneyland and it will always be in my heart, but DisneyWorld ROCKS!!! Even my DH was planning our next trip on the flight home!!! LOL Good luck, and feel free to PM me if you have more specific questions. Oh, one more thing. You can compare the costs on disney.com/travel Another great site is allears.net