This is the year I kiss Windows good-bye. Well, maybe not entirely, but the writing is on the wall for Microsoft's flagship operating system, and all other desktop bloatware: The future of PC software is open source. (I'll add that the future of PC applications is on the Web, which I'll cover once we've got Ubuntu in place.)
Being the belts-and-suspenders type, I'll make the conversion from proprietary to open in baby steps, the first of which is to get a copy of Ubuntu 7.1 (a.k.a. Gutsy Gibbon), the version of Linux from Canonical Ltd. that has a reputation for being complete, well supported, and easy to use. I know the OS only by reputation, however. Wikipedia provides a comprehensive comparison of Linux versions.