You'll be best off setting up Windows on a 10 Gb partition, and Mandrake on a 10 Gb partition. Take the remaining 20 Gb's, and format them using FAT32 so that both O/S's have access. That 3rd partition is where you'll store all your documents, downloads, etc., and both Windows and Linux will be able to use them. Don't forget to install OpenOffice on both 10 Gb partitions so that you can access documents in either O/S. Make sure also that you turn off Plug 'n' Play in the BIOS before installing. It will save you some headaches down the road.
That should get you started. Lanman
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