OK so U messed up the installation
U installed GRUB in the mbr instead of the boot partition (not a big deal) This is why when U reboot U only see GRUB (The Linux Booter).
Is it possible that during installation U deleted a partition?
By default Fedora (and RHEL) don't include NTFS support, that's why U can't see those partitions under Linux.
On the other hand there are no disks or partitions in linux visible only directories. Go to the /mnt dir how many subdirs are there? There shuld be one for every floppy and CD\DVD drive U have plus one for each fat partition.
On the other hand if Windows doesn't appear in Grub get yourself a bootable CD (knoppix, ubuntu or better yet a WinPE like ERD Commander) and check to see if your Windows partition egsist.