Hope you have installed both windows and linux on the same hard drive.
While running linux, the windows folders will not be visible.
This is because in windows, the files will be in the FAT file-system;
In linux there will ext2fs file-system.
e.g: to view D:drive
[root@AGRAJA ~]#mount -t vfat /dev/sda5 /mnt/wind
Note: there should be a directory named wind under mnt folder.
The contents of the wind folder will be that of the D:drive.
This can be copied to some other location say /home/test.
After copying the mounted files can be unmounted using the following command:
[root@AGRAJA ~]#umount /dev/sda5