It's theoretically possible to fine-tune your picture with just your eyeballs and instincts. But if you want to get it right, you should use a DVD-based calibration tool. Here are three worth considering.
THX Optimizer: You probably already have this one, since it comes on every commercial DVD with a THX logo. But you don't have all of it. Some of the Optimizer's tests require special blue glasses that you must buy via mail order. The glasses cost only $2, plus an additional $2.50 for shipping and handling.
THX offers a decent set of test patterns, although they're not as complete and well explained as some stand-alone products. Nor are the written instructions as helpful as the narrated ones on stand-alone discs.
Not surprisingly, considering THX's background in cinematic audio, the Optimizer can also help you set up your surround-sound system.
Imaging Science Foundation HDTV Calibration Wizard: Cocreated by Imaging Science, Microsoft, and Monster Cable, this disc manages to walk you through calibration without using a bunch of unnecessary tech jargon. The narration by singer Jenna Drey helps; she comes off like a regular person, explaining the calibration process in plain, understandable English.
Another advantage: The HDTV Calibration Wizard uses live video instead of test patterns; they're easier to look at, and they give you a better sense of what your TV's picture will look like. For instance, to set the black level (an extremely important setting that almost always has to be fixed), you get a close-up of a man's black shirt and coat, and you simply adjust the setting until you can see the difference between the two.
Monster sells the Wizard for $30.
Digital Video Essentials: Although it isn't as easy to use as the HDTV Calibration Wizard, Joe Kane Productions' DVD offers the most exhaustively complete consumer-level calibration tool I've seen. Not only does it walk you through video calibration, but it also helps you set up your audio and the room environment, as well.
Sometimes this disc is a little too thorough, however, with the narrator explaining so many technical details that it's easy to lose track of what you're supposed to be looking for. Mastered in 2001 and released in 2003, it's also a bit outdated--for instance, it operates under the assumption that most HDTVs are CRTs.
JKP sells newer, more up-to-date Blu-ray and HD DVD calibration discs, but has no newer offering that you can run on a conventional DVD player. The company sells the older DVD for $25.