The title of the thread makes it seem like you think older games can't be played without the better graphics and gameplay, but I think older ones are good as they are.
However... maybe some of the old, old, old DOS games like amulets and armor(google it, elder scrolls like game), would make a great remake. A lot of those games need to come to light as new, since PC gaming wasn't big back in the late 80s, early 90s.