You can reset the Preferences of your browser. They're probably on the Edit menu. Once you've called up the Preferences window, look for something labeled "Colors" or "Web Content" or "HTML Display".
Books aren't usually printed on gray paper--for good reason. A lighter background provides more contrast and makes reading easier. On the other hand, pure white may be too bright. I prefer something around 95% lightness (vs. the default gray's 80% and pure white's 100%).
Links stand out more if they are red, rather than the default blue. Blue is more appropriate for visited links.
Underlining makes text harder to read. If links are a different color, you should be able to recognize them without underlining. Uncheck the box labeled "Underline links".
To see what I'm talking about, check out this link.For more advice about setting browser preferences, see Web Wonk.
There are other browsers available. I'm using iCab for Macintosh.
Many WYSIWYG editors generate code containing deprecated tags and outright errors. Besides, what you see isn't necessarily what you get anyway, since different browsers display the same page differently.
I create my pages on a Macintosh with BBEdit, and check the syntax with BBEdit and iCab.