Old Metal Gears? You mean pre PS1? They suck, and hard. They aren't even challenging games, they are just awful, as are many NES/SNES games that were at one point in time considered good.
With that said, I might hop into the world of Fallout 3 again. I really don't need any time consuming games right now, though, so I'm really on the fence about starting that up.
No I meant the Ps1 games not the NES/SNES ones