Hi Stuart86uk, welcome to the site
To keep confusion to a minimum, we have a "one member's question per thread" policy in our forums. If you need help in the future, you should start your own thread and ask your question(s) there.
I'll answer the questions you've already asked here, though:
1. The 32-bit version of Mandrake should run just fine on a 64-bit platform. It obviously won't be able to take full advantage of the 64-bit architecture, but even so, some users have reported that their 32-bit Linux installs have run slightly faster on 64-bit machines.
2. Your stranger in the lab coat was referring to the fact that Mandy has traditionally been the most Windows-like distro in terms of "look and feel", making it a good introductory distro for users coming from the Windows world. That isn't as much the case any more though, as many other distros now use GUI environments that are very "point-n-click", and include setup "wizards" and other such windows-ish "ease of use" features. SuSE and Fedora definitely fall into this category.
Many hard-core Linux users will tell you that those are "toy" distros, because they do most of the work for you, but IMNSHO that is a Good Thing for Linux newcomers. The point that those poeple often forget though, is the fact you don't
have to use the graphical goodies to accomplish tasks; if you want to get your hands dirty by hand-hacking your configuration files, compiling your own drivers from source, etc., you can do that with
any distro.