It isn't only possible to partitionate and formatate you can also just see which distributions you have, how they are formatated and how much unused space they have.
(After saving your data) you can with GParted also reduce partitions to create others.

There are a view thing you should know when you work with linux.
You may not have more than 4 primary partitions per HDD.
Usually the first (which is also bootpartition) is used for Windows if you want multiboot solution.
In the second Primary (which works as an extended Partition) there will be implemented the virtual Partitions (for data and/or linuxes)
the third Primary is used for Linux-Swap
The fourth Primary is traditionally kept free for Solaris.

Linux counts hda1 to hda4 for the Primaries and starts with hda5 for the virtual Partitions.
So often you don't have a hda4 even if you have hda5 and hda6.


Linux doesn't have problems with FAT and NTFS but Windows does have problems with ext3 and so on.
That's way a datapartition should be ntfs so you have access from both OSs.

If you know this you will see GParted is a full graphical program very simple to use.


But whenever you don't understand something with linux please feel free to ask - therefor there is the forum.