You can do this one of 2 ways. First, you can use a third party utility such as Partition Magic or Symantec's Volume Manager to manage or merge partitions. Many people swear by these utilities, but I've had mixed results and usually stay away from them. You could also upgrade the XP volume to use dynamic disks via the DISKPART utility, which will allow you more freedom to merge and resize disks. Again, I've had mixed results with dynamic disks in Windows XP and avoid using them. The other option is to do a full backup to an external source (tape or external hard drive), delete the partitions and restore the data from the backup.
This was first published in March 2004