Don't forget that when you resize your image down, keep the dpi ( print/output)resolution at a max of 300 dpi , your prints will come out fine at this res ( the industry standard is about 286 dpi( at profesional labs) so 300 dpi means you can easily print your images back up from say 6x4 to 10x8.
hope this helps a ittle.
Also, as others have said, get as much information in your camera ( high meg taking format) every time if you intend to print anything in the future.