There are a number of reasons for wanting to make an SD memory card bootable. You may want to install an operating system, such as Windows Vista or Ubuntu Linux, onto the card and run it using USB. Or you can load boot utilities onto the card to help fix problems with your computer at system start-up. Whatever the reason, you can make any SD card bootable in Windows XP.
Download and install PEBuilder (see Resources). This is a free utility for creating a pre-installed environment for Windows, allowing you to boot from an SD card or USB drive.
Insert your SD card and open "My Computer." Right-click on your SD card and select "Format Drive." This formats the SD card to a file system capable of booting from SD.
Launch PEBuilder. Under "Source," choose the file you want to be bootable. Click "Build" and wait for the process to complete. When you restart your computer, press the key to enter system BIOS (it's different on every computer, but commonly Esc, F1, F2, F10 or F12). Go to "Boot Order" and change "External Storage Device" as "Primary." Save the changes and restart. Your system now boots directly into the SD card.