Overall a Linux based platform can perform most of the tasks equally as well as a proprietary platform using the likes of Ubuntu and its derivative distros. However Linux does have its limitations with some applications and in particular gaming.
I thoroughly recommend Linux Mint 11. Its easy to install and easy to use plus it comes with much of the software you are likely to need preinstalled.
Linux Mint 11 Download
http://www.linuxmint.com/edition.php?id=81
Linux Mint Installation Guide
http://www.linuxbsdos.com/2009/12/03/linux-mint-8-installation-guide/
How To Dual Boot Linux Mint and Windows 7
http://www.linuxbsdos.com/2010/12/08/how-to-dual-boot-linux-mint-10-and-windows-7/
Linux Mint 11 Release Notes/User Guide
http://linuxmint.com/rel_katya.php
You download the ISO. image of Linux Mint 11 then you need to create a Bootable LiveDVD for installation
https://help.ubuntu.com/community/BurningIsoHowto
Linux Mint 11 can also be run straight from the LiveDVD from Boot without touching your Hard Drive
LUg.