When you install CentOS with windows in dual boot environment.By default you wont be able to mount the ntfs file system.Here is how to mount it.

1.Open terminal with root account.
2.Then install rpmforge

rpm -Uvh http://packages.sw.be/rpmforge-release/rpmforge-release-0.5.2-2.el6.rf.x86_64.rpm
yum install fuse-ntfs-3g