Ah--the good ol' Linux vs Windows debate. Hands down--Windows is better. There are more installations of Windows out there than Linux--it's better.
Windows and Linux both have their places. It really depends on hardware and software requirements. While Linux does work on most desktops, have fun getting all your hardware devices (like wireless) to work. Hardware manufacturers are notorious for not providing Linux drivers. Want to be able to print on your 8 year old HP Laserjet on Linux--you'll probably have no problem. Want to print on your brand new HP P1102w--have fun with that. Found a program you want to install but there's no package for it--have fun installing it from source and getting through dependency hell.
Like I said--Linux and Windows have their places. If you need enterprise directory support, flawless application integration, etc.--Windows will be your choice. If you want to do your own thing, have total control of your system, and build it from scratch, Linux will be your choice. If you decide to go the Linux route, learn to use it from the CLI first. That's the real power of Linux. If you install Ubuntu and just use it like you would Windows, then you'll never really learn how to use your system.