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. For example I retain a dedicated Windows partition to run specific applications such as Office 2010 etc.
http://www.linuxbsdos.com/2011/01/28/dual-booting-windows-7-and-ubuntu-10-10/
Installing Ubuntu as a dual-boot with Windows without partitioning
https://help.ubuntu.com/community/Wubi
Download Ubuntu Desktop Edition Windows Installer
http://www.ubuntu.com/download/ubuntu/windows-installer
Ubuntu 11.04 (Natty Narwhal) User Guide
http://ubuntuguide.org/wiki/Ubuntu:Natty
I thoroughly recommend Linux Mint 9 LTS which is built upon Ubuntu 10.04 LTS its easy to install and easy to use plus it comes with much of the software you are likely to need preinstalled
Linux Mint has a similar installer called mint4win (mint4win works the same as the Ubuntu Windows installer so the instructions outlined above are almost identical)
Linux Mint 9 LTS Download
http://www.linuxmint.com/edition.php?id=52
Linux Mint 9 LTS User Guide
http://www.linuxmint.com/rel_isadora.php
You download the ISO. image of Linux Mint 9 LTS then you need to create a Bootable LiveCD for installation
https://help.ubuntu.com/community/BurningIsoHowto
Linux Mint 9 LTS can also be run straight from the LiveCD from Boot without touching your Hard Drive
LUg.