We live in so cal and are AP passholders. We go to
disneyland at least 5-6 times a year and usually stay in hotels.
We just returned from a 5 day disney trip. I would reccommend 2nd week of January and 5 nights. There is a new attraction there (if you have a girl) called Princess Fantasy Faire, that alone you could spend 3 hours there. My 5 year old LOVED it. There are several great shows and parades that could easily take up the remainder of 2 days. Allowing you 2 full days for rides. I would expect that week of the year for the lines to be less than 30 minutes. We have president's day in January, I would try to avoid that weekend, as it makes it a 3 day weekend and the crowds will increase significantly.
As far as hotels, we never stay on property. Unlike DW, where off property is 15 minutes away, DL only has 3 hotels and the remaining couple of dozen surround it.
We just stayed at the hilton, I won't do it again, didn't care for it. I have always like the marriot and the shuttle comes every 20 minutes. We have always found it easy and convienent. We have stayed at the Fairfield which you can walk to disney, and it was adequate, but no restaurant onsite. there is a great coffee shop Millie's in the parking lot. A little furthur about 2 miles in Garden Grove (shuttle goes there too) is the Hyatt, which IMO is definately one of the nicer properties in the area. there are no true 5 stars in that immediate area. The question is what quality of accomodations and ammenities are you looking for?
We went last year for 2 weeks in DW at the Beach Club. Was the property nice? Absolutely was it worth it $4500? I don't think so, I wouldn't do it again. So the question is, is it worth it to pay $350 a night to stay onsite, when you will be mostly sleeping there?
Other parks:
Legoland and Sea World in SD. SD has many many nice hotels to stay at. Knott's is pretty run down and nothing like Disney. Although if your kids like snoopy might be worth a trip. as far as the zoo goes, you are making a long trip out here to see a zoo where we have Koala bears as main interest?