to check if your windows drive is mounted, simply start a terminal and type:
That one will give you a lot of extra partitions, so it can be hard to se if you don't know what you are looking for. To list out partitions of ntfs filesystem, type this insted:
mount | grep ntfs
If your drive is unmounted, you could do something like this:
If you want to write to the partition, you have to install ntfs-3g (I'm not sure if it comes as default in rhel5).
If you only need to read from the partition, you can mount it (usualy without any any need to add modules to the kernel). First figure out what partition it is, to do so, use fdisk or cfdisk. Make a folder to mount the partition to, mkdir /media/ntfs or something else describing. If your partitions name is i.e. /dev/sda1, you can mount it like this:
mount -t ntfs -o umask=000 /dev/sda1 /media/ntfs.