Well, actually, I'm talking about the automatic 32x32 cropping that the system does. I can change the CSS, but when I upload and image larger than 32x32, Vanilla will always resize it.
Ah, so it's the Account Pictures extension you are wondering about? I haven't used it myself, but the extension page says that "you can change the icon and picture sizes on the settings tab" (as pbear pointed out).
Comments
Account Pictures?: should be in preferences
Attachments?: also in preferences