The recovery partition can be used to restore your computer to its factory defaults. The recovery partition would allow you to reinstall Windows as well as any other software that was bundled with the system. It is safe to remove, although if you ever needed to reinstall you would need to do so with an OS disk or bootable flash drive.
If you're comfortable with removing it you can simply right-click on the partition in Disk Management and choose the option to Delete Volume. After doing this, you could then right-click on your C: partition and choose to extend the volume.