"If you have a bunch of video files, then you probably also have a bunch of video and audio codecs (Divx, Xvid, MPEG-4, AC3, etc.) to match. Most of the time when you don't have a particular codec installed, either the video or audio stream won't render, and you can diagnose which codec you need and install it.

Windows Vista decides to throw you a generic "COM Surrogate has stopped working" or "DLLHost has stopped working" error message when it can't find some of your codecs. Vista's updated Media Center will completely crash without any error if it encounters a file without the proper codec (not very appliance-like if you ask me). This usually occurs when trying to get the video thumbnail, so you can have a hard time navigating to other video files if you step upon this "land mine."