To Install >1 Linux versions on same HDD

Hello there!! I wish to install more than one versions of linux(viz. Fedora3/RHL9 and Mandrake10) on same HDD.I own a Seagate SATA 80GB HDD and an AMD64 2800+ CPU.I believe we can accomplish the above task by having a common swap file for both versions and different natives.For booting we can choose to boot from floppy when we can supply the kernel of the desired version.Also could you please tell me how to configure linux to work on 64bit platform?Please,if possible,tell something about the drivers required for install.