After you install Ubuntu in dual boot with windows it is necessary to have Read/Write access to your old files on NTFS partition. When you install Feisty, it mounts your NTFS partitions Read only. Here is how to get write access to the partition.
Click on Applications/Add-remove.
Type NTFS in the search box and select all available applications in show box.
You will find NTFS Configuration Tool, select it to install and click apply.
After the utility is installed click on Applications/System Tools/NTFS Configuration Tool.
Check the required boxes and click ok.