My parents took my brother and I to Disney World when we were about 10 and 12. It was a weird age, because we felt like we were "too old" for disney at the time. I remember a few things: I wasn't super excited to go, but thought "hey, at least I'll see Mickey." I was wrong. My parents didn't plan anything at all! We didn't stay on site, we didn't meet a single character, we waiting in long lines, it was kinda bad. My mom had got us tickets for multiple days and we only ended up doing the one because we didn't want to stay longer. Another thing I will never forget from that trip was my mom forcing me to go on Space Mountain. I REALLY didn't want to. She insisted. I cried. I remember making eye contact with the CM there pleading with them to not let me go on. I went on, and I didn't like it.
I went back at 29 years old, with my boyfriend, and had the GREATEST trip ever. We stayed on site, got the dining plan, did character meals, met MICKEY, got fastpasses, went early march when it wasn't boiling hot.
Best of all, I went on Space Mountain, and absolutely loved it.