Just a note - even though San Diego doesn't sound that far away from Anaheim, traffic is unpredictable. It's feasible that the drive could take you 4 hours, depending on what time you are on the road. You can literally have stop and go traffic for 40 miles or more!
Southern California doesn't really have the best setup for mass transit, I would rent a car.
Everyone wants to see the Walk of Fame in Hollywood, but it's really not the nicest neighborhood. I had some guests that just had to go, and they were happy to get out of there after a couple hours. With the limited time you have, I would skip it unless you really want to do it. I would then do one of the organized tours.
Knott's is fairly close to DLR, but just remember it isn't "Disney". I'm disappointed when I go there, and keep comparing it to DLR. But, it does have a lot of thrill rides. If you like those, this is the place to go. And make sure to have the fried chicken dinner.
I wouldn't bother with the LA Zoo, if you go to the SD Zoo. Totally different league!
You would want at least 2 days at DLR. I can do 3-4 days without a problem, and I'm a local. Not sure what your interests are, but there are some good shopping areas in OC.
Bret's Disneyland Lodging LinkMap
There are a lot of hotel/motels on Harbor Blvd near DLR. Park Vue Inn 1570 S. Harbor Blvd is the closest off property "hotel". (Most of these hotels are really motels, or at least that's what they feel like.) Park Vue is closer to the exit than Disneyland Hotel. Stay within "200" of this address, and you can walk to DLR. (1300 - 1700ish Harbor Blvd.)
Be careful of any hotels not in this address spread, because they can claim to be right next to DLR, but they are on the back end where there are no entrances and you have to walk 1/2 mile or more to get to the actual entrance. If you have a car, and plan to drive to the resort, then there are plenty of choices. I personally don't like to hassle with the parking structure, parking lot trams if I don't have to. (plus the $10 parking fee per day.)