I leave my font at this default setting any time I'm writing content text for my web pages. If you want to use a certain style of font like Comic Sans, Futura, etc. This is the only way to make the font look the same for everyone. Xara offers a program called Xara Webstyle that allows you to create your own graphics, banners, bullets, buttons, and backgrounds using graphic templates no matter what your skill level. Otherwise, your web page may look messy and will be totally unformatted if you use fonts other people may not have.
Some fonts are very difficult to read.
When writing long copy, consider the fact that your reader may wear glasses and have difficulty reading, and that reading fancy writing actually places strain on the eyes. Remember, you're writing to a potential customer, and you want to make reading your website as pleasant as possible. I visited a site once that was written completely in cursive. The site had long text paragraphs and all was written in fancy cursive writing. It was very difficult to read and tough on my eyes.