Given the age of your kids I would say the DLH is a good choice. The DLH is the most Disney themed of the three with the best themed pool. However, I will just list some information of each resort from my experiences and let you decide for yourself!
DLH: Very spacious rooms that sleep five very easily. Each room will either have a daybed or provide you with a free rollaway. Wonderful, themed Neverland Pool with two slides and a large hottub area. You can grab quick, inexpensive snacks, burgers etc from Crocs bits n bites that is right there at the pool. They also have a small coffee shop that is nice for morning offerings. There is a sliding door to allow fresh air in but no balcony to sit on. I have stayed at several of the resorts at WDW (ASMO, ASSP, ASMU, POR, POFQ, BWV, SSR, Pop) and I still think the DLH is my favorite resort, Disney or non Disney anywhere. It just feels so magical and being walking distance to the parks is so nice (but of course all three onsite properties at DL offer that perk). The DLH has the lovliest grounds of the three onsite hotels with waterfalls and koi ponds. You can rent little remote control boats, your boys would probably love. The DLH also has the best arcade of the three hotels. Very small laundry room however, with only two lousy washers.
PP: Really large rooms with very comfortable daybeds. You can pay an upgrade to receive a themepark view which I highly recommend. Its not as big of an upgrade fee as you would pay to receive say a MK view at the CR. Only one tower so you don't have to navigate through grounds or worry that you are getting in a building located where you don't want to be! Some people have experienced slow elevators here, I haven't in my two stays but can see how it can happen. They do have a glass elevator which is neat, esp. at night but that can be a long wait as they only have one. It is the least themed of the three hotels but does have some cool beach and Disney touches. Not many dining options, both of our stays the pool bar has been closed which is a bummer. Square pool, not exciting or Disney themed at all but with a very cool slide similar to Boardwalk's. It is the longest walk to and from the parks but not by much over the DLH. Taking the monorail from
Disneyland or cutting through the GCH from DCA saves time and feet. It is the cheapest of the three. The arcade at PP is sorry and very expensive! The windows in the rooms do not open and there are no grounds to speak of at this hotel. It also does not have a laundry room.
GCH: Location, location, location! It is no nice to be right inside DCA, especially to change out of wet clothes from the Grizzly River Rapids ride! The rooms are the smallest, they do have some bunkbed rooms (that include a trundle) and some daybeds. They will also provide you with a sleeping bag. They offer nightly turndown service for all guests which is very nice. It is the most "wow factor" of the three, but not in a Disney way. It is very similar to WL. Nice pool, not Disney themed with two slides, kiddie pool, main pool and another pool as well. They have Whitewater Snacks which is the best place of any of the three hotels for a burger or light meal. They have endless hallways so if you are not near an elevator be prepared for a trek (reminds me of Boardwalk)! The customer service at this hotel was excellent. The rooms have little in the way of Disney theming and they are a bit dark. They almost all have balconies which is so nice! The rooms are smaller than the DLH or PP. To me the balconies, nightly turndown and customer service as well as the location make this one a real winner. But I missed the Disney theming of the DLH! And the parking lot is huge, my brother was staying there when we were and he had to park clear by Paradise Pier, not a big deal since he never moved the car one time but I thought I would mention it. Also, there is no arcade at this hotel. They do have a laundry room with maybe six washers and about 8 dryers.
I love staying onsite at Disneyland. I know many people say its not a big deal and I don't think it is as much as WDW, but I still think it adds to the trip. And with crowds, getting Early Entry each day its offered is a huge perk! You also get package delivery, room charging priviliges in the park, themed pools with slides and that Disney customer service.
I hope this helps! There is a sticky on the top of this board with information and pictures of all three hotels. Good luck with your choice!
It reminds me of vacations when I was a kid to Yellowstone! It does have a very big comfy resort feel to it. The view rooms are the best IMO. The balconies are also great to have. We spent a lot of relaxing time on ours overlooking Grizzly River Rapids. It is also the most expensive of the three resorts, which sometimes plays a role on if we stay there. Depending on the time of year too. 
I'm sure mine would be fighting over who got to sleep on the floor as well. They also would love the no brushing teeth on vacation too. The thing is even with one of them sleeping on the floor my aunt and I would have to share a bed since I don't think either of us could sleep on the trundle that pulls out from the bunk beds.
I'm thinking that a split stay between DLH and GC would be fun. Maybe 3 nights at each. I'll certainly remember to utilize VP when I make our reservations I know IP at Poly and AKL were top notch. One of my twins favorite game is a DIsney game he made up its call "Where is ....." He names a ride at WDW and you have to name the park, and when the ride is in the MK saying MK isn't good enough you have to name the specific land. He is really funny. He and his older brother pretend the shower stall is TOT and they "escort " you in and give you the TOT speech. My oldest is 5 and he has been asking to go to Walt's home (what he calls 
