I'm pretty sure you'll see the fireworks at PI from Saratoga.
NYE at the parks isn't too bad. I've been there on several NYE's, including 1999-2000. I'd stay away from the MK that night though, it gets scary-crowded on Main St. and in front of the castle. Epcot isn't bad and only gets jammed at the usual congestion points. If you just stay put once you find a comfortable spot and don't try to take a leisurely stroll around World Showcase between 10:30PM - 12:30AM you'll be fine. The crowd dies down considerably after that.