Looks like maybe a scanned copy of a picture or is it vector? What does the the info bar state the dpi is when you bring it in to Xara if it is a scanned copy. Any method you mentioned is fine but I might think about exporting it as .tiff file if you are taking it down to your local digital print shop as Jpeg always have some form of losses in quality. Also most drawings will print well down to 150 dpi if you stretch your drawing but remember to put your aspect lock on.