For screen display you want low resolution and small file sizes for faster downloads. For print you'll want to keep all the resolution and pixels you can get.
More Desktop Publishing Quick Tips
- Avoid "lossy" compression formats such as JPG for your screen captures.
- If exporting a file containing screen captures to PDF, turn off the automatic graphics compression in your Distiller options.
- Don't let your software change the resolution of your images (turn off any such options) before sending your document to the printer.

