I'm betting that's supposed to say 800x600. Typos happen sometimes.
In any case, there is a widescreen patch floating around out there, it came out 4 or 5 years ago IIRC. It's a bit... unpolished, though. It requires the Conquerors expansion and a no-CD cracked copy of the original game (though let's be realistic, anybody who still plays AoE II already meets those requirements), there are different patches specific to particular resolutions and only a limited choice of resolutions, the menu screens are not re-sized at all, and the bottom toolbar in the in-game window isn't properly re-sized either (as can be seen here). I mean, it works, but I prefer just playing the game in windowed mode instead.
So the 'HD edition' does have some definite improvements in that regard. The textures have also been upgraded, though there are some mods out there that can do the same to the original game (I've never tried those, don't know how good they are). Still, taking a 15 year old game, doing a few little tweaks, slapping DRM onto it and charging $20? No. Fuck them.