Okay, here is a rundown of the fireworks, etc.
Magic Kingdom: Fireworks are the Wishes! Spectacular. From what I understand, you see them best at the California Grill and Narcossee's. You can eat dinner (request a later dinner reservation), then you go out on the balcony, they dim the lights and play the wishes music. I've heard both are great views of the fireworks, never been though.
Epcot: Fireworks are Illuminations. This is a ground pyrotech show plus fireworks, so while you can see some fireworks from the boardwalk, you cannot see the ground effects. This one isn't as disney-esque as wishes is, but amazing anyways. I suggest getting a dinner at Rose & Crown Pub (again, make a later dinner reservation). last year, they held our food for us till after the fireworks, and we were allowed on their private balcony to view the fireworks. it was a wonderful, non crowded view, and when we left, there were no crowds to beat, because we still had to eat & pay.
DHS: Fantasmic! Is a night time pyro/water spectacular show. It is amazing, and much more thematic (thus why it's at DHS), than Wishes or Illuminations. You can do a dining package, where you get dinner at Mama Melrose, Hollywood Brown Derby or Hollywood and vine, then get VIP seating at Fantasmic. Personally, I'm not sure if it's worth it, depending on what night & what showing you go to.
There's my run down..anyone have any places to add?