Hi, mari360!
I spent this past New Year's at WDW with my family. There were 12 of us. We were there Dec. 28-Jan. 5. Crowds are going to be extremely high while you're there, but if you go prepared and expecting a lot of people, you should be okay. I'm glad we went and got experience NYE at Epcot, but I'm not sure I need to ever do it again. The parks will stay open later that week, which is a plus. We spend NYE at Epcot and had a lot of fun. Each country celebrates their new year at the time it is midnight in their country. We were in the UK section at 7pm and celebrated NYE with them. At midnight they have a great big party, but we didn't stay that long. The Christmas decorations will still be up for you to see. They'll start taking them down in stages sometime after the 1st. You might want to read my Trip Report. Just click the link at the bottom of my post. Have fun!