Yet another potentially confusing issue here is the gamma control a few TVs are now starting to carry. Playing around with this can again have a significant impact on the way the colour elements in your picture relate to each other, and should be used with care. It's widely considered that a 2.2 Gamma setting works best/gives the most natural results with TVs, so if your TV offers that as an option, go for it, at least as a starting point.
Few TVs actually offer precise gamma values like this, though, instead just using a sliding scale of gamma adjustment. If you really want to mess with this, make sure you do so with an image onscreen that contains a wide variety of different colours and tones, so that you don't end up over-emphasising one tone over others.
With so much subjectivity where colours are concerned, people really interested in achieving something like an objectively accurate colour palette from their TV should definitely invest in Digital Video Essentials, which uses its own proprietary colour test signal in conjunction with a set of three colour filters you hold in front of your eyes to help you adjust each of the three primary (red, green and blue) colours.
The idea is simply that while looking through the filters, you tweak your TV's colour settings until the ‘background' colour of the picture matches the reference colour ‘box' in the test signal.
If your TV has a colour management feature that lets you adjust the primary colours individually, then this test signal is relatively easy to use. But thanks to the provided filters, even people with just a single colour adjustment on their TV can fine-tune that setting while focussing on just one colour at a time.
You should always start with the Blue setting here, as in an ideal world, once you've got this set right, the red and green colours should automatically ‘click into place' if a TV's colour decoders are working correctly. In reality, however, few TV colour decoders are as accurate as they should be, so if your TV allows you to adjust individual colours, it's definitely worth checking the red and green filters too.