I don't get it. The original game has these handmade, prerendered graphics, mostly they don't scroll right to left (though a few screens do). What should a "widescreen" version show on the sides?
It's like asking for The Starry Night in 16:9... sorry, van Gogh is dead.
I think you are speaking of the advenure games Indiana Jones and the Fate of Atlantis or Indiana Jones an the Last Crusade but the guys above talk about Indiana Jones and the Emperor's Tomb which is a 3D game.
Btw. I'm interested in a solution for running the game in my native widescreen resolution too ;)