The resolution is OK for the pic 72dpi but its only 152 pixels wide. It says 550x375 on your pic which would be much better size if you have it at that.
PS will send some seeds next week to you Franco, I have a few types for you
Franco, click on the first forum link in image shack. Do not click on the thumbnail links. Before you submit to the forum preview it, if happy subbmit.