Install NTFS configuration tool and when you open it for first time you will get an option to enable write support on NTFS partitions you have - internal or external.
You can also select which partitions you want to enable support by default.
For example, I have three NTFS partitions - one of which is Windows 7 C: drive and one other is Windows 7 boot loader partition. I enabled write support only for C: drive and not the bootloader by default. Doing this will also auto-mount the partitions for you (by the time Ubuntu boots up). You don't need to mount them each time, if you use this tool.
Go to Software Center and search for NTFS and you will find this one in the list. Just install it and open it, you will understand what to do. I use Gparted too, but I don't think that the problem is with Gparted or something else. NTFS partitions give some trouble sometimes.
Read these for more explanation if the software center doesn't show NTFS tool in its repositories (which I think might be the case with 11.10):
How do I enable NTFS write support?
Adding NTFS-Write capability by default
ntfs-3g
, otherwise it might not work. – Thomas Ward Jul 03 '12 at 18:44