Windows XP came with a reasonable partition manager, however it didn't let you resize partitions like the new Vista version can do. The new options of shrink and extend allow you to resize active partitions, something that required 3rd party software until now.
To load this application, run
compmgmt.msc from the command line and select Disk Management from the left hand menu.
Not only can you format, delete and resize partitions but you can also change drive letters with a few clicks. If you install a new DVD drive at a later date but want to rename the drive letter, simply right click on the drive and select "Change Drive Letter and Paths" and then click change. From this menu you can pick another available drive letter.
