According to Microsoft, "All font files are registered under a single key in the registry, and a registry key cannot exceed 64KB." Microsoft estimates that you can install between 1,000 and 1,500 TrueType fonts. Sound ridiculous? Depends on the user. But the general consensus on the Web is that anything beyond 200 to 300 fonts will slow your system.
Fonts affect Windows startup
Since Windows keeps all of the fonts in the Registry, the more fonts you have, the more adversely it affects the speed of your Windows startup. If you actually have 1,000 fonts in your system, you probably noticed that Windows takes longer than usual to boot.
To speed up your startup, try removing some fonts (you never actually used Andale Mono anyway).
To view all the fonts on your computer:
Click Start, point to Settings, click Control Panel, and then double-click Fonts.
This opens the Fonts folder, a system folder that displays all your fonts and lets you see what they look like.
Wait a second before you go hog wild and start deleting fonts. There are a few fonts that you cannot delete. They are system fonts, and Windows uses them.
To find out which fonts are your system fonts, you need to know which version of Windows you are running. To do this:
Click on My Computer and select Properties. The General tab should be open (if not, click on it). Record what is noted under "System." View the fonts on your computer by using the steps above. Switch the view to Details, which should list the fonts alphabetically. You want the information listed under Modified. Now look at Microsoft's webpage on how to determine the default Windows fonts. Find the version of Windows that matches your own. Microsoft lists a system date for each version (for example, Windows 98, build 4.10.1998 has a system date of 5/11/98). Record that date. Go back to your Fonts folder. Any font that has the same date as your system date is a system font. Do not delete this font.
An alternate way to find out which system fonts should remain on your system is to visit this webpage. Locate your version of Windows in the pulldown menu and it will bring up a list of system fonts for you.
To delete a font from your computer:
Click Start, point to Settings, click Control Panel, and then double-click Fonts to open the Fonts folder. Click the icon for the font you want to delete. On the File menu, click Delete. To select more than one font to delete, hold down the CTRL key, and then click each of the fonts you want to delete.