For the DVD and possibly the floppy issues, you may find the answer in the thread link here
. To see all partitions Mandriva has access to, look at /etc/fstab file, it will list all partitions visible. If you need to access any of them listed here, let us know which one and the particulars of the partition. In Mandriva, usually you will find a graphical utility displaying all partitions being used called "kdiskfree" which can be found through the main menu.