need help loading mandrake 9.1 over mandrake 7.1

[anxiety]

I have tried several distros of linux and keep coming back to mandrake. I had lindows laoded and wanted to change, had to format my hard drive ib bios to get rid of it. Went to load Mandrake 9.1 (on cd) and kept getting invalid systen disk, had my computer set to boot from cdrom. I was able to load a copy of version 7.1, now what do I do to load version 9.1,
The 9.1 is an iso that I downloaded and burned as an iso. Any hepl will be greatly appreciated.
Thanks,

[zeeone]

I would have to say, your ISO copy is bad, back -up and try again.

[anxiety]

I had the software on a dvd, and burned 3 copies as ISO and none would work, Finally broke down and bought a cheap ( $25.00) dvd drive and was able to get it loaded. Now to get it hooked to my network, so I can go online. My other 2 computers are winxp, but think I can get the wireless thing going. Linux has improved a lot in that area. Thanks for your reply