You can run 32bit versions perfectly fine on AMD64 hardware, just like you would with windows.
The only difference is that you take a slight performance hit ( <5%) and you can't have more then 4gigs of RAM (without hacks). With AMD64 you have the streamlined instruction set (doesn't mean much to a normal user) and the ability to run massive amounts of RAM.
If you want to you can run 32bit versions, I don't think you would be able to tell the difference if you sat a 32bit Linux OS next to a 64bit OS and compared, unless your running a database or a large server or something like that.
Suse is a bit funny. For a long long time they DID NOT have a install cdrom you could download. They have a netinstall cdrom were you boot the computer off of the cdrom and download the packages from ftp servers as you need them, instead of off the cdrom. It's a bit difficult at first, but you get used to it quickly.
If you want mandrake here is were you can download Mandrake 10 for x86-64 (AMD64).
<a target=_blank class=ftalternatingbarlinklarge href="ftp://mirror.cs.wisc.edu/pub/m.../devel/iso/10.0/amd64/">ftp://mirror.cs.wisc.edu/pu......el/iso/10.0/amd64/</a>
AMD64 versions tend to lag behind i586 (regular 32bit version) versions a bit, Right now version 10.1 is the newest mandrake version out for i585, but 10.1 for x86-64 is still in the "release canadate" stage, which means that it's not considured entirely stable yet.
10.1 for i586 (32bit PC's)
ftp://mirror.cs.wisc.edu/pub/m...x/devel/iso/10.1/i586/
If your going to use Mandrake, join the mandrakeclub if you'd like. It'll allow you privilaged access to the newest versions as they get released, before they get released to the general public.
For Suse here is one
netinstall howto
for the i386 (for 32bit x86 machines) go here for the boot disk
<a target=_blank class=ftalternatingbarlinklarge href="ftp://ftp.suse.com/pub/suse/i386/current/boot/">ftp://ftp.suse.com/pub/suse/i386/current/boot/</a>
<a target=_blank class=ftalternatingbarlinklarge href="ftp://ftp.suse.com/pub/suse/x86_64/current/boot/">ftp://ftp.suse.com/pub/suse/x86_64/current/boot/</a>
Be sure to choose a mirror near you... ftp.suse.com is located in germany and will probably be slow and busy. You can speed up the time if you substitute the ftp sites for someplace close to you. Also after you choose a mirror write down the mirror and the path to the installation packages, because they may change slightly.
Good luck.
And if all that is to complicated or to much of a hassle right now. Check out Knoppix. It's a Debian based OS that boots off of the cdrom and it doesn't require any files to be installed on your harddrive to run.
. Then you can head on down to 
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