The i386 folder contains a complete copy of your Windows installation files. In fact, if you look on your original Windows install CD, you will find the exact same i386 folder on it. So why should you keep it on your hard drive, too?

The answer is that whenever you connect a piece of hardware to your computer, it will search for the correct driver to "talk" to the hardware. For instance, if you connect a new mouse, Windows will search for the files it needs to communicate with the mouse. These files are in the i386 folder. Most times, it will search in there automatically, find the correct files, and just work - all without any intervention from you.

However, if you delete the i386 folder, your PC won't know where the needed files are. So it will pop-up a box asking you for your Windows CD. Every time. Trust us - it gets annoying. Not only will you have to keep your Windows CD nearby anytime you use your computer, but you will also have to make sure that it never gets scratched or damaged - if it does, you are out of luck.

Keeping the i386 folder on your hard drive frees you from worrying about the CD. Keep the CD in a safe place, and only bring it out if Windows suffers a catastrophic failure. You won't have that extra space on your hard drive, but you'll be much happier in the long run.