I've done it every which way in the last couple of years and I'm never tired of doing more and more pictures. First, I like doing somewhat of a travelogue by pictures. I make sure every place we hit including resorts, restaurants, souvenir shops, etc. are included. I've even done pics of menus. Two of my favorite shops on the inside are the
Disney store in Downtown Disney and the shop for China in Epcot. I love taking pictures of signs throughout the parks along the route we take. Animal Kingdom is probably the best for signs but Epcot is pretty good, too. Every trip I come back with at least 500 pictures and I've topped 1000 pics on a trip. Digital camera is my favorite new toy.
I love doing the entertainers at the parks. This includes the informal and formal shows. Waiting areas for rides can be very amusing. Test Track and Buzz Lightyear are among my favorites in this category. I get views of the parades that have wonderful backdrops like MK with the castle in it or the Tree of Life with the AK parade floats. For the parade floats, I usually take three pics per float. One is far away and then a little closer and then on top of you. Don't forget ceilings in certain attractions like the Temple in China at Epcot is gorgeous. At Epcot's WS I love getting there just as they open. It's pretty deserted and you can get some empty street pics if you move fast. My thing with WS is to get a big picture of the country overall. Then before I get in a country I zoom in to particular buildings. Once, I'm in a country then I'll do each place there including the shops.
I love different, weird angles of all the building attractions at all the parks. Take pics on a slant upwards rather then straight on. I've been known to lie on the floor or ground and take a picture. Take train and boat rides to get pictures that way. Make sure you take night pictures, too. Spectromagic is my favorite for night.
Finally, as mentioned previously don't forget yourself and family. I agree the candid shots are best. There are many CMs that will take a group shot for you. I do live through my lens on some trips but there are plenty of trips I don't even take a camera. Enjoy the memories.