Turning next to colours, the from-the-box settings between different TVs can be really diverse - though again, there's a widespread tendency for all TVs to have colour saturations set way too high in their from-the-box state, so that that they jump out at you from shop shelves. (Or so that they hide some weaknesses a TV might have in the greyscale department…)
So if you're going to go it alone, the first thing you'll want to do is nudge down colour settings to around 40-45 per cent with LCD TVs, maybe a bit higher for some plasma TVs. It's a good idea here to have someone's skin on screen in a reasonably bright scene while you make your adjustments, as getting a skin tone that looks right is usually a reasonable focus point. That said, don't be so slavish about skin tones that you focus on them at the expense of all other tones; no tone should look dominant over all the others, for instance.
Also, ironically, I'd generally recommend that you actually avoid any specific ‘fleshtone' settings some TVs carry, as these tend to work on certain tones in isolation, which can lead to an unhappy colour balance over all.
Another key adjustment at this stage is colour temperature - the ‘base level', if you like, of your TV's colours. Most TVs now have a colour temperature setting, and how this is configured can have a major impact on your picture's appearance.
Although the colour temperature terminology is usually the same for most TVs' colour temperature settings - you usually get Cool, Normal/Standard, and Warm, sometimes with an extra Warm further option - the actual colour tone ‘values' of these settings can vary considerably from brand to brand.
One thing that I can recommend as a near universal truth is that you should avoid all Cool settings. These can actually look quite instantly attractive on some TVs, with their crisp whites. But don't be deceived; the tones they reproduce elsewhere across the colour spectrum will be some way removed from any sort of video accuracy.
Choosing between Warm and Normal/Standard settings is a tougher call. If you're calibrating a screen for near-exclusive playback of films, you might want to go for the Warm setting; certainly this is often selected by the ‘Movie' or ‘Film' picture presets many TVs carry.
But at the risk of aggravating the die-hard calibrators out there, I suspect that some people will find many TVs' warm colour temperatures look too reddish or orange, especially with plasma TVs. And if this applies to you, then I don't expect you to stick with a warm setting just because you're told you're supposed to. As I said before, while it's perfectly sensible to calibrate a TV towards some notion of a perfect, objective accuracy, this should never be allowed to stand in the way of your personal enjoyment.
In fact, colour temperature settings are, in my opinion, the single most subjective matter of personal taste of all the TV settings. Tastes on colour temperature even appear to have a national perspective; for instance, I have heard much talk in the industry of how Germans prefer a warm tone (as is reflected in the presets of the TVs from German brand Loewe), while Americans tend to prefer a quite cool tone.