I've always thought that colorized films were a fun alternative to the original, when done correctly. Unfortunately, when the process first started, many times the job wasn't done right at all. Luckily, as technology has improved, so has the work on this sort of thing. For instance:

It's pretty obvious which one was done later.

Note that I said alternative; I believe that it should be a bonus feature at best, and nothing more. The current DVD/Blu of It's a Wonderful Life got this right by including a modern colorization done by Legend Film.