As for going to Disneyland in April be warned that April is prime Spring Break time for the Pacific Northwest. So...more than likely it will be busy. But if you utilize your fast pass you should be fine. Like before you eat lunch get a fast pass to the ride you want to go on next and when your finished with lunch you should be able to get on the ride pretty fast. One of the best places I like to eat at DCA is Taste Pilot Grill. It is next to Soaring Over California and it has the best burgers in the park with a fresh Burger Condiment Bar. Have a great time and have a Disney Day
My best tip for you would be to avoid the weeks surrounding Easter. This is when most of the So Cal schools have their spring breaks. (Including mine, going from Good Friday through Easter week.)
It should be busy, but if you avoid those two weeks (last of March, first of April) you should be in a much better situation then if you went during that time, which has huge crowds.
We are planning on the middle to the end of April. Luckily that is when my son will be off-track. We don't have a traditional spring break since we have year-round school here.
We did our off-track trip to Dland April 22-25 in 2001 and it was FANTASTIC!! Wonderful weather SHORT lines-I can't think of a more perfect time to go,Enjoy!!!