As someone who has been to both DLR and WDW multiple times, I'll try to help you. These are just my opinions, though.
1) I book directly through Disney since it is easiest for us. We drive in, though, so we don't need more than a room and tickets. If you book through AAA you get an enhanced FastPass which, I believe, gives you the option of getting multiple FPs at once.
2) We usually stay at the Grand Californian. It is sort of a cross between Wilderness Lodge (architecture) and one of the Epcot resorts (so close, you can easily walk to either park and dont need any transportation). DL is kind of like a theme park that takes up a big city block, in the middle of town, not like how WDW is surrounded by Disney property. There are hotels and motels all around it. If you are used to taking a shuttle bus at WDW and dont mind it, almost all the hotels around DL will do. If you want to walk, DLH and GC are great. There are other, non-Disney ones, that are walking distance as well, but I dont know their names. We stay at the GC because we usually only stay for a couple of nights and like the location. It is expensive, though.
3) DL gets pretty crowded during school vacations. It is a small (in size) park, so it can get very congested. However, it has lots of attractions (way more than MK), so the lines for each ride can be tolerable. We do the early morning tour, afternoon pool, evening tour schedule and it worked great.
4)Things not to miss -- I dont know what ages this is for, but:
--Biggest Dont Miss of DL -- Indiana Jones! Huge ride, with the ride vehicles of Dinosaur at AK, but much better theme, sights to see. I hate this type of ride but will go on this one because it is so cool!
--If you like POTC -- this version is better, longer and more fun. There really is a big difference.
--Dining at the Blue Bayou inside the POTC ride -- so cool!
--All the little rides in Fantasyland that just dont exist in the MK. (Alice in Wonderland, Storybookland Canal Boats, etc.) And the Matterhorn, which isn't really little.
--The Aladdin show at DCA -- it's really great!
--Depending on your budget, you can get reserved seating (and a dessert buffet) for Fantasmic! The show is similar, but different, to the one at WDW. It takes place on the Rivers of America, though, and there is NO seating at all for it. People just stand at the river edge and in all the surrounding walkways to view it. (This makes for scary crowds!) We did the balcony dessert seating once as a treat and it was really fun, and yummy!
--The Tiki Show without the new management is still playing in DL.
Hope this helps -- and have a great trip!
