Reference:
http://www.himeyashop.com/howtoplay.phpPC Windows XP Users
Many users of the English versions of Windows XP play imported Japanese PC games by setting up Windows XP to display Japanese text.
1. Go into the Windows XP's Control Panel.
2. Open the [Regional and Language Options].
3. Click on the [Advanced] tab.
4. Select [Japanese] from the pull-down menu at the [Language for non-Unicode Programs] section.
5. Japanese will display for all non-Unicode programs then (Windows restart required).
Below is additional information on setting up. Some games are required to do this.
1. Open the [Regional and Language Options].
2. Click on the [Regional Options] tab.
3. Select [Japanese] from the pull-down menu at the [Standards and Formats] section.
Some Japanese PC games may also have a region checker when they install, though this can be bypassed by downloading and using Microsoft's AppLocale program. Information on where to download it for Windows XP and instructions on how to use it can be found here:
http://www.microsoft.com/globaldev/tools/apploc.mspxNote: If you've never dealt with this before, you'll need to install the Far East Language Pack prior, and then these instructions will apply. Image is attached below. You check that box, click OK, provide your Windows XP disc, and properly point the dialog boxes you'll receive to the disc, etc. (This only needs to be done once.)
Also note: If you're still running Windows 98/ME, you need to upgrade. Period. Windows 2000 on the other hand does support booting in Japanese mode, though.