To do your picture profile, did you upload directly from your computer or did you link a hosted picture?
For the signature, I am pretty sure you have to be using a hosted picture and do the [img] and [/img] around the url to the hosting site. I don't think you can directly upload for the signature.
Photobucket will both resize and generate the code for you. Imageshack generates the code for you but insists that the pic be zipped before it will accept it.
Dinan chip, Bilstein sports w H&R, RD sways, RD strut brace, 750 bushings, Zimmermans/MetalMasters, O.E. M Pars, Eisenmann muffler