On my laptop, I have a partition containing the original Windows XP partition resized down to make room for everything else, a Linux partition (Fedora) that is my "primary" OS, 2 additional partitions (one EXT3 and one NTFS formatted), and I can "dual boot" using GRUB into either.
I've left the original XP partition virtually untouched, and I generally boot into Linux, where I've installed Sun VirtualBox. Under VirtualBox, I have 3 VM's configured - the XP installation I normally use when I need Windows, a Fedora install in a VM so that I don't have to worry about crashing the whole system if I want to dink around with trying stuff out, and a Vista installation so that I can see what Vista users see when I need to help someone with a Vista issue.
It's a bit "techy" getting a Grub dual boot set up, but it's way do-able. The biggest problem in fact was getting WIFI working under Linux. The USB Verizon EVDO connection which I figured was probably no way, no how - turned out to be no problem at all.
I should probably find time to mess with Ubuntu one of these days, as that seems to be the (disclaimer, in own reserved opinion - don't crucify me if you feel otherwise!!!) distro that is percolating to the surface as the most popular these days - but other things have been taking my time. (Not an endorsement or judgement on which is better - Fedora, Ubuntu or any other!)
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