You can change the drive letter in Windows XP Computer Management.
To open Computer Management, click Start, and then click Control Panel. Double-click Administrative Tools, and then double-click Computer Management.
In the console tree, click Disk Management.
Computer Management (Local)
Right-click a partition, logical drive, or volume, and then click Change Drive Letter and Paths.
Do one of the following:
To assign a drive letter, click Add, click the drive letter you want to use, and then click OK.
To modify a drive letter, click it, click Change, click the drive letter you want to use, and then click OK.
To remove a drive letter, click it, and then click Remove.