I've had a blast trying out the different distros. If I get bored I just grab a LiveCD of another one and clean install, restore my pics/documents (saved onto a CD-R) and my music (saved to a DVD-R) and away I go.
If you really get bored try Vista greatest POS yet from the Mickey Dees of OSs.
But I still have a dual boot with XP on my laptop because there are some things for which there is no suitable (for me) substitute in the Ubuntu repositories. I have to have MS Streets & Trips and my Quickbooks. I still keep my “official” email and calendar in my Outlook but use Evolution and keep the messages on the server until the next time I start Outlook, which can be days at a time. But I was able to also write a complete business case for a client complete with financials in the Open Office 2.2 Calc (Excel equivalent), a 30 page document in Open Office Writer and associated presentation in Impress (Powerpoint equivalent). Of course I exported it all to MS Office for the client, but I just wanted to see how well Open Office on Linux worked in a business environment and it worked very well.
Ubuntu, Linux and the free software movement is coming along very nicely.