With the interest of creating a roguelike RPG (such as Nethack, Rogue, and ADOM), which programming language would be most suitable and why?
With the language that you choose, be sure to list any libraries or facets of the language that make it particularly well-suited.
Way back in the day I tried to write Roguelike games using QuickBASIC out of all things (it was 1988.) Not the recommended approach...
There are still some development circles out there. Here's an FAQ on Roguelike Development and also a blog dedicated to the same.