JFR, I have had the same question, discussed it on the Canon forum and was adviced by experienced users. The answer to your question is yes, you are right, the best way for cropping is to uncheck resample box, leave the box "dpi" blank and get the "original" pixels. After cropping you should to check the image size and corresponding resolution. If it is more than 200 dpi, your pictures are ready to print. If it is less, you should check the box "resample" and input the resolution f.e. 300 dpi. I process my shots according to this procedure and the results are pretty good.

Regards - Andrzej (G3)