We are Disney nuts. Scratch that, my wife is a Disney nut.
I go to Disney twice a year. My wife 4 or 5 times per year. 90% of our trips are to Orlando, the rest is DisneyLand or international. (We've been to Paris and Tokyo) We don't have any kids.
DW in Orlando is so much better I can't even put it into words adequately, but I'll make a list of some reasons :
- The cast members are infinitely better, there is more "Disney Magic"
- It's much bigger (in terms of space). I actually feel claustrophobic at DisneyLand due to how cramped everything is.
- Magic Kingdom > DisneyLand
- Hollywood Studios >>> California Adventure. (We haven't been to the new Marvel land, but have tickets for December)
- Disney Springs >>>>> Downtown Disney in CA
- Animal Kingdom and Epcot don't have comparisons in California. Epcot is our favorite park, but understand how it may not be a destination for those with kids. Animal Kingdom has Pandora/Avatar that you can't get anywhere else
- Resorts in Orlando are destinations by themselves. Some have restaurants better than anything in DisneyLand.
- Transportation - busses run from all resorts to all parks. At DisneyLand it was a long walk from our hotel with homeless people to pass by.
- DW is cleaner, better kept up and feels newer.
- Totally immersive. Disney has control of the whole area. At DisneyLand they sometimes run into issues with the city of Anaheim - for example, they had to cancel one of our half marathons because Anaheim revoked their permit or something like that.
- Universal Studios is not far away if you want to spend a day there. (We had a big Harry Potter fan join us on one trip)
Now, all that being said, it sounds like you guys might just want Disney to be part of the trip, and not the whole trip, which may lend DisneyLand to work better for you guys. I think you'd miss out on some of the magic, but I'm guessing 6 and 8 year old girls may not understand the difference between the two experiences anyway since they're not going to do both. AND your wife wants to go to California.
TLDR : DisneyWorld is better, but DisneyLand sounds like it might be better for you guys in your situation.