the GLX driver will suit for both i386 and i686 architecture, don't worry about that.
Use xconfigurator to configure your x-window, you can choose your screen resolution and frequency at some stage. (:-)
For your LILO, because i haven't played with it for long time, so i don't dare to give you any advice. You better search the web. But i am surprised you still got Windows NT on your machine. You sure it is not Win2000 or WinXP? I am running Linux and winXP on my notebook. I choose to install bootloader at MBR, it works fine.