In the admin CP i see you can edit how many images and all that but is there any way i can make it a certain size? I keep getting people with sigs that are background sized =\
Are you meaning limiting the size of the images?
There is a Character Limit for Sigs but there is no limit on Image Sizes.
A thing I do on my board is stick signatures inside a <div> with the max-height and max-width property set.
Problem with that is that large (in terms of filesize) images aren't blocked, and I think IE6 doesn't support the max-width and max-height properties. For the last issue, you can set a fixed width/height property, but people without a signature will just have a big blank space.