Yeah, the toddler age is fun in it's own special way. I really liked when my daughter hit 2.5, as I felt like we could have a conversation.
I used to teach dance and the youngest I worked with were 7 year olds. From there up is really fun to me. Especially teens (when they aren't yours).
Yes, conversations with preschoolers are usually amusing. Really, once they're no longer babies and they can actually
do things, I like kids (well, smart kids) at pretty much any age.
There's an age around 10-12 years old that I'm a bit uncomfortable to meet for the first time in a large group, such as meeting a classroom full of middle-schoolers all at once. This is when kids are likeliest to be mean. (My thing from that conversation over in the Girl Chat section becomes relevant here.) If some or all of them already know me, then it's usually okay. But going in cold is intimidating (as embarrassing as that is to admit!)... fortunately, I don't have to spend too much time in middle school classrooms. None in the past 7 years, in fact.