One LiveCD, Sabayon, ran perfectly on my mates laptop (Beryl and all) when I had to run it in safe graphics mode on my blindingly fast Vista machine! I understand now that even powerful laptops use fairly standard hardware so the developers of Sabayon were able to make it fully compatible with most laptops. In contrast desktops can have millions of different pieces of hardware in even more different configurations!
I had heard good things about Ubuntu so I asked for a free CD (A good way of getting into Linux without downloading the ISOs for hours) but the 6.2 disk I ordered wouldn't even run! Luckily they fixed this in 7.10 and I'm very happy with my installation of Gutsy Gibbon! As you can see from the screen shots below I got Compiz Fusion running, without much trouble, and I even have it optimized for my 32" LCD TV.
Although it was far easier to get Vista configured for my TV when you configure something in Linux you feel like you've achieved something, windows always seems to molly coddle a user holding their hand through every option with Linux you feel in control, powerful but still safe. I tried installing the screenletts sidebar recently and nearly broke Ubuntu, but the safety mesh stepped in and told me that what I was trying to do was dangerous long before I did any damage.
But if Ubuntu's so great why do I still have Vista? One word iTunes, I've got an iPod Touch which requires iTunes 7.5 (or whatever the latest version is) to sync but wine (a windows compatibility layer) doesn't support it yet. You can get the touch to sync with Amarok but it involves a lot of work and at the moment I'm quite happy to wait for the wine developers to do their magic.