You don't need a new TV to view widescreen, it just leaves a black band on the top and bottom of the screen.
My personal opinion is that pan and scan versions "full screen" versions, end up cutting images out of the screen that the director intended you to see. Often, during conversations, what you lose is the reactions of one of the people in the conversation who was cut out in favor of the speaker.
In action or visual sequences, you lose details off on the sides that may actually mean something or be clues to what's going on...or just nice "local color."
Editted to add:
Additionally, fullscreen versions are re-editted to fit your screen by some hack who didn't have enough talent, vision, drive, etc. to actually be a director or feature editor. So take that for what it's worth.