Your present primary partition has Windows running on it? That was the question asked there with your mention of two partitions seeing Windows installed. First you have to know the size of the partition you are currently running this copy of Windows on. You do that by opening up the MyComputer link or folder seen in Windows Explorer or simply double click on the MyComputer desktop to see the drives installed.
You simply right click on the C and D if second partition to see how much is used or free space and add the total to see how large each parition is there. What you are doing is displaying the properties of each logical drive seen on the one hard drive. If you have a 120gb drive one could be 60gb while the other is 54+gb. With GParted or the Disk Management tool you can delete the second partition once you know which one it is. GParted will clearly to the second one as "HDa2" as the second partition while the DM sees the drive letter assigned only.
The second question is partially answered now with adding one other thing to that. The Disk Management tool in XP and not even in Vista can create a new partition on a drive. The installer when booting with the Windows install disk of either readily can where you then exit the installer after to cancel an unnecessary installation. Once in the DM in either XP or Vista you can now right click on the partition selected to choose the full format option(recommended) or the "quick format". The links here show what the DM looks like in Vista with four hard drives not one with the last being formatted following that seeing GParted create the new single partition there.
Right click on drive for choosing the format option,
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You will note that the previous screen there shows some 8mb of free space empty on the XP Home primary ide drive. While performing the full format on the second sata drive the 8mb space saw that swallowed up with Vista's not XP's ability to increase the size of any partition.
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I could easily booted with either the XP or Vista installation disk to see the partition created on the newly added sata. But GParted can do that as well as resizing or moving partitions. Microsoft finally catching onto that with the new ability to shrink or grow partitions now added to both the options on the installation and the Disk Management tool. The one thing GParted can't do is format any partition. That's why the DM is used when having more then one drive installed on a system. While the DM is formatting a slave drive you can be busy doing other things.
http://img241.imageshack.us/my.php?i...nfirmedvm2.jpg