..any of them can use Linux/Unix, provided you have drivers and a means to install the OS.
what do you mean by "means to install the os"? what would not constitute "means"?
what can be said about 64-bit *Nix'es versus 32-bit versions?
aslo, let me add that i want to use the laptop to practice programming -- C++, Java, scripting-- so the laptop will need to support emacs, lint and other ancillaries, and -- preferably, not required -- a compiler.