Well, I kept looking and have solutions. Thanks, everyone!
I've checked out the magnifying glass tool and it's not very usable, though if you were desperate it might be ok.
Glasses I already have.
Lowering the screen resolution is not an option if I want Solidworks and everything else to be normally functional, but one guy suggested running a second monitor, and setting it at lower resolution. This I did, and though my desk is more crowded, it's a fine solution, and pretty handy in general for keeping other windows visible for reference.
And some The help files are compiled using HTML help, so they obey your Internet Explorer settings. The help files use a 9pt Verdana font.
If you find that this isn't big enough, there is one workaround. Unfortunately, or fotunately (depending on how you perceive it), this change will also affect the font on any web page you view with Internet Explorer.
In Internet Explorer: A. Click Tools, Internent Options. B. Click 'Accessibility'. C. Select 'Ignore font sizes specified on Web pages'. D. Click OK twice. E. Click View, Text Size and pick one of the text sizing options.
Steps B and C were what I hadn't figured out. You have to close and reopen the Solidworks Help window for the change to take effect.