Hopefully, Buzz will step in and give you the scoop on the CSR. He has tons of information and pictures. Don't know who the Pop Century expert is but I'm sure somebody will be able to give you lots of information.
Have you gone to www.allearsnet.com and checked out the pictures? Click on accommodations and scroll down to the resort of your choice. Click on slide show to view the pictures.
I would say POP because of the theming unless you have children that get overstimulated easily. We took DD there when she was 6 and she loved it but last year we went to CSR and she likes it better now. The rooms are a little bigger than POP and there are alot less children there.
I have stayed at both resorts and will tell you that the bus system at Coronado Springs is better. There is 5 bus stops around the resort. Carrying small children from the main bus stop at Pop to the back of the resort is not fun. CSR is a beautiful resort and my sons loved the quite pool. We stayed in the cabanas 9b. We are staying at CSR again in November.
I have stayed at values before (not POP though) and I was not at all impressed. the rooms are so-so and it seems very loud. For just a little more money you get the feeling of a wondefully themed resort with many dining options and a great pool!
DBF and I have stayed at Pop 3 times (2003, 2004 & 2005) and are staying there again for our December trip We LOVE Pop. The themeing is great; it's different decades with icons specifically from those decades. hippie: 60's has tye dye, peace signs etc... ) The main pool in the 60's buildings, which are the preferred buildings, is huge and has flowers that spray water. They also have a kiddie pool as well as a kid's play area with pop jets. When you walk in the front doors to the lobby, there is also a kids sitting area with a TV that shows Disney movies and cartoons, so the kids can sit and wait while mom or dad checks in. Outside the front doors they have hula hoops and sidewalk chalk to write messages on the sidewalk! I've also seen the CM's get a hula hoop contest going!! The food court is huge and so is the gift shop. At certain times (I believe once in the morning and once around dinner time) the CM's in the food court do the Twist and The Hustle!! I'ts a riot!! The bus service is very good. I personally don't ever remember waiting longer than 10-15 minutes for a bus. I love Pop; I think you'd have a great time there!
My kids LOVED Pop, but I prefer the moderates mainly because they are a little quieter. If you don't mind the noise, Pop would be fine. Otherwise I don't think you could go wrong with either.