Goofy's is a great roller coaster for small kids (or roller coaster weenies like me). It is a pretty short ride with several stops. The theming is cute and you get a nice view at the top. You can usually ride it repeatedly with very little wait for the first hour after the park opens - after that you need a FP as the line moves pretty slowly.
I agree with HydroGuy that Little Mermaid isn't blow your mind good, but it's cute. It's a good one for little kids (my kids went on it about 15 times on our last trip). It's also a continuous loader so the line (if there is one) moves quickly. You rarely have to wait long and it's a great ride to escape the heat and crowds.
World of Color is a beautiful show using water, lights, projections and music. Totally worth checking out. If you are really into it and want to get that "perfect" view, you'll be investing a few hours of your time, no matter how you get your Fastpass. If you are OK with a decent view, or are very, very tall (like 7 foot 9), you can show up a few minutes before showtime.