I use Georgia and I have used Bookman at times. They are both reasonably open styles and look good on both a screen and paper. The old standard is Times New Ro

I use Georgia and I have used Bookman at times. They are both reasonably open styles and look good on both a screen and paper. The old standard is Times New Roman, but Times was designed for legibility while cramming as much text into a newspaper column as possible. I think it looks cramped.