I suggest you read the Mandrake Starter doc
you can get it here - html or pdf
There is a very good step by step guide to installing
Check your disks, it sounds like they're corrupt
you may have burnt them too fast - choose a lower speed
here is a good how-to to burning with nero
How to Burn a CD using Nero
Version 6 (Ultra)
--- Step 1 Launch Nero.
--- Step 2 Select "Copy and Backup" icon near top right of dialog box.
--- Step 3 Choose "Burn Image to Disc"
--- Step 4 Choose "Image Files (x.nrg;x.iso;x.cue)" from the "Files of type:" drop-down list.
--- Step 5 Navigate to the .iso file. Dbl-click on it or select it and choose "Open" button.
--- Step 6 Choose the "Write Speed" and "Number of copies" values on the Image Recording dialog box. Click Next.
--- Step 7 If you don't have a CD in the drive, Nero will ask you for one. Otherwise, Nero begins the burn process.
--- Step 8 Unless there was a problem, you're done. Nero has a couple of more screens.
Version 5.5 or earlier
--- Step 1 Insert a blank CD into the CD writer
--- Step 2 Launch Nero.
--- Step 3 In the File menu, select "Burn CD image".
--- Step 4 Choose as file type: all files (.), since Nero expects files with the NRG suffix.
--- Step 5 Select the ISO image file
--- Step 6 You will see a dialog box asking if you want to supply detailed image parameters.
(for later versions, these are the default values)
Enter the following parameters:
* Type of image: Data Mode 1
* Block size: 2048 bytes per sector
* File precursor and image trailer: 0 length
* No scrambled and no Swapped.
--- Step 7 Click on "burn". If the program complains that there are errors in the image file, click on the button "Ignore" and launch the burning.