FC5 doesn't have native ntfs support. So do what I tell you and It should work. Cause if you create another FAT32 Partition as a workaround you'll suddenly figure out that the max. filesize is 2GB.
1st create a directory within mnt using mkdir
mkdir /mnt/win (for example)
2nd check your kernel version with
3rd go on this Link
and download the RPM matching to your kernel version
4rd issue the command as ROOT with "su -" it includes the PATH Variables...
fdisk -l (l like language)
It will show you the partitions with NTFS Filesystems
after you've done the steps 1-4
5th Install the rpm with (below it's just an example for my kernel)
rpm -ivh kernel-module-ntfs-2.6.17-1.2174_FC5-2.1.27-0.rr.10.5.i586.rpm
6. mount the partition in your Linux tree
mount -t ntfs /dev/sda3 /mnt/win
(You'll need to asign probably another device then sda3 depends on the output of fdisk -l )
7. check with
if it was mounted correct
8. If you want include it to your /etc/fstab so that you don't have to do the step 6 everytime.