This is a bigger topic than you might imagine.
Printing (whether on your own ink jet printer, preparation of an art print, or submission to a publication, etc.) means conversion to CMYK color space, even if you don't explicitly invoke this step yourself. CMYK has a different (and much more restricted) gamut of colors, as well as limitations in inking. There may be colors in your RGB image that are not printable in CMYK - look for an explanation point (!) in the information palette when you scan around the image in RGB or LAB.
Things with weird names and acronyms like dot gain, GCR and UCR get invoked, and it turns out have huge implications for how a printed version of your image will actually look. None of these are trivial.
Resolution is another issue, but it's not the case that, for printing, more resolution is better - sometimes the opposite is true! And there's also aspect ratio. Your original digital image might have an aspect ratio of 1.5:1. You might want to crop this differently to display it on the web, and you definitely will want to crop to a different aspect ratio if you're printing on A4 or US-standard paper sizes and want to make maximal use of the printable area available from your printer. You'll want to set the pixels/inch setting to 72 for images you are using on the web, but for printing you will probably want to go to 200 or higher.
As for me, I try to do all editing at the maximum resolution/file size the original image has. Images for the web get converted to 72 dpi and a maximum size of 800 pixels on the longest side - usually 800 x 535 for an uncropped image. To print, I go back to the original large file, set dpi to somewhere between 200-300, and crop the image to fit on A4 paper.
Robert Delfs