Size of the bird doesn't really matter.
One question though,,,you know how people play with thier birds outside of their cage won't the bird like fly away?haha
EDIT: Nvm I forgot you have to clip thei wings.
And I would like a bird that makes nice sounds haha
Jake thanks you for the complement. She's actually female, despite her name. I thought she was male for the first two years I had her, and then decided to get her DNA sexed to see if she really was male. Oops.
The species of bird really depends on a lot of things. How much time you can devote (keeping in mind that even small parrots such as budgies can live 15+ years), how much space you have for a cage, noise tolerance etc...
I would recommend Cockatiels. Any bird needs LOTS of care and time. If you don't give them the time they'll make sure you pay with squawking etc.lol They're extremely intelligent. Yeah, we had our Cockatiels feathers clipped so she wouldn't fly around the house and hurt herself. We bought her a huge Macaw's cage so she had plenty of room to move around in and when we were home we'd leave the door open and she'd climb right up onto the top that had a little pole for her to sit on. She loved being on my shoulder though, never once pooped on me. :)
Oh and when she was younger I used to bring her outside and let her sit on a low tree branch. She LOVED it.