Personally, I think any of the DLR hotels are perfectly great for various reasons. I would look at all of them and pick the one that looks the best to you and fits in your budget.
CGH - Location location location, literally a few steps from California Adventure and about a 5 minute walk to the front gates of
Disneyland. The only DLR hotel that has rooms with balconies. Rooms are a little smaller than the rooms at the DLR or the PPH. Gorgeous lobby. Craftsman architecture and theming.
DLH - Large rooms (being refurbed now and the new rooms are gorgeous with headboards that light up), most rooms have sofa beds, beautiful grounds with waterfalls and ponds galore, 3 minute walk to the DTD monorail station. DTD view rooms will have a nice view of the Disneyland fireworks. Disney themed with Mickey Mouse touches. Here is a picture of the new rooms (you may be able to guarantee a newly refurbed room if you reserve a DTD view room, but I'm not positive on that):
PPH - Large rooms, most rooms have sofa beds, and the most bang for your buck (given that it's the lowest priced DLR hotel). A 5-6 minute walk to the DTD monorail station and a 6-7 minute walk to the private entrance (located in the GCH) of California Adventure. Upper themepark view rooms should have a nice view of the new World of Color show. Beach/nautical/surfing themed with Disney touches. Here is a picture of one of the rooms (doesn't come with the kids - hahaha):