Settlers of Catan there is precious little backstabbing, since it is hard to know what your competitors' goals actually are, which I think makes for a much more friendly game.
The "Europe" edition has interesting variants on the basic edition, though I'm not completely sure they are all for the better. Other than a denser map (it is Europe, after all), there are three new elements in place: Some routes (ferries) require locomotives, some routes (tunnels) are variable cost, and players have a choice of adding "train stations" to make use of other players routes. These extra flourishes add to the decisions one makes, but I'm not sure they actually improve the game. If you are new to TtR, I'd suggest starting with the basic edition -- but, if you are an experienced player looking for a slightly more complex spin on an old favorite, you might want to check this one out.