Although TrueType fonts take up considerably less disk space than the other font types, you're still looking at anywhere from 30–120KB per font file. If you have hundreds of fonts, the numbers can add up to a big chunk of hard disk acreage in a hurry. Also, all your installed fonts take up memory, whether you use them or not.
To keep a lid on both hard disk and memory usage, you should periodically clean out those font files you never use. To do this, just delete the appropriate font files from the Fonts folder.
DISABLING OLD FONTS
If you'd like to keep your old fonts around but not have them load when you start Windows 98, just move them to another folder. Windows 98 will remove the fonts from the Registry, so they won't load ...