I chose dog, but I think pets are rarely worth the trouble.
I chose Guinea Pig and here is my reasoning:
I do not care for cats, I have about 20 stray/ferrel cats that live in my yard and they make a mess everywhere, it has pretty much turned me off of cats forever.
I think a dog would be too time consuming and would require too much attention, and we are never home to give it the attention it would need.
Lizards, gross. :)
Birds, loud :)
So process of elimination I went with Guinea Pig. I have owned a hamster before and I enjoyed it. Did not enjoy cleaning the cage though.
I hope this helps you and good luck.
Cats also cool!
I love my puppy, too, but I have to say my kitty is still my favorite. The puppy still has a little too much energy for me.
I have always love dogs. They are a wonderful companion and very loyal to you. They are fun to play too!!! =)