Hi Carol,
Our favorite dining spot in all of WDW is the Contemporary Grill. If possible, book it during the MK fireworks...they dim the lights and pipe in the music into the restaurant. Alternately, you can walk out onto the balcony and watch. Our favorite character meals were at the Grand Floridian and Crystal Palace. It really depends on the characters you want to see. The pontoon cruise would be a good option since the crowds will be big during the summer and finding a good viewing spot would be tougher without staking out the spot an hour or two in advance.
If you do one of the Disney water parks, go early. By late morning all the chairs are usually taken up and it's pretty packed. Blizzard Beach is my favorite park but tends to be busier because it's newer and has more thrilling attractions. Typhoon Lagoon is more laid back.
On tour plans, don't bother. The BEST thing you can do is get to the parks early...avoid them if possible in mid day (hot, humid) and then go back out in the evening. I personally also avoid the Early Entry parks, or if I go, I leave them by 11 am and go to another park. Ride the Fastpass attractions early, get Fastpasses as soon as your window opens up. Save the non-Fastpass attractions, especially the indoor air conditioned ones, for the hottest parts of the day. As an example, Hall of Presidents, American Adventure are great respites.