I knew I forgot something!
What you need to do is copy the files while that XP installation isn't running. There are several possible ways to do this:
1. If your boot partition is FAT, you can use a boot diskette, and copy the files as you would in DOS.
2. I use ERD Commander, from Winternals. It's sorta pricey, though.
3. You can try the recovery console. It's limited in what it can do, so I'm not sure if it will let you copy files into the fonts directory. But it's free, and therefore worth a try.
4. You can install Windows on another partition. This is the official Microsoft way to do it, and it's a pain. It's most likely to work though.
No matter which way you do it, start off with the new fonts in an easily accessible directory, like C:\FONTS or something like that.
You are false data.