I will third this! I really like my 18-105 for basic photography such as birthday parties and family functions. It gives you a little reach and yet is wide enough to get group shots. If I don't want to "get fancy" that's what I use. The 35 1.8 would be great for your parade shots and dark rides. Those two alone would be a nice light, set up. What I would not do is get another kit lens.
So what you do is you tell your hubby the "experts" say you should get the 18-200 for convenience at Disney but you were thinking for just a little over half of that price you could get these
two. They'd still be light and easy to carry and what a bargain!

The trick is to show him the 18-200mm and it's price FIRST. He'll be so relieved when he sees the price of the other two combined he'll want to get those for you!