The easist way to "try" Linux, or to use it professionally, is via virtualization on Windows XP/Vista.
Download free VMWARE Player: http://www.vmware.com/products/player/
And Fedora Core 7 pre-installed image: http://www.thoughtpolice.co.uk/vmware/
Within few minutes, you will run Linux on Windows (with 99% of native performance)
I use it daily, work on Windows Vista, as it has the best UI and best /most SW available, but also run Linux inside virtual machine (VMWARE) to have MySQL, PHP and Apache in the same environment (=Linux) as my webhosting. No need for a separate server anymore.
Can use excellent Outlook 2007, Dreamweaver CS3, Photoshop CS3, DX9/10 games, while developing on native Linux x64 machine, running in the second window; have best of both worlds available...