Linux and Viruses
http://www.whylinuxisbetter.net/items/viruses/index.php?lang=
Linux and Security
http://www.whylinuxisbetter.net/items/security/index.php?lang=
Having read the information above this does not mean Linux is immune
http://www.linux.com/learn/tutorials/284124-myth-busting-is-linux-immune-to-viruses
Overall a Linux based platform can certainly perform most of the tasks equally as well as a Windows based 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 alongside Linux Mint I retain a partition with XP on to run specific applications which cannot be adapted through a Windows compatability layer such as Dreamweaver CS5, Office 2007 etc.
http://apcmag.com/how_to_dual_boot_windows_xp_and_linux_xp_installed_first.htm
If you intend to continue to run a number of Windows applications I suggest Dual Booting
Installing Linux as a dual-boot with Windows without partitioning
http://psychocats.net/ubuntu/wubi
I thoroughly recommend Linux Mint 10 Main Edition which is built upon Ubuntu 10.10 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)
You keep Windows as it is, mint4win only adds an extra option to boot into Linux Mint. mint4win does not require you to modify the partitions of your PC, or to use a different bootloader, and does not install special drivers. It works just like any other application.
mint4win keeps most of the files in one folder, and if you do not like it, you can simply uninstall it as any other application.
Boot in to windows insert the Linux Mint LiveCD and you will offered the option of installing inside windows which is where the mint4win installer comes in, you will be asked how many gigabytes you wish to allocate to Linux Mint (I recommend 8gb) then you set a password for your installation then click install and thats it.
Once Linux Mint is fully installed upon starting your PC you will be given a choice of which operating system you want to use Windows or Linux Mint
Linux Mint 10 Download
http://www.linuxmint.com/edition.php?id=67
Linux Mint 10 User Guide
http://linuxmint.com/rel_julia.php
You download the ISO. image of Linux Mint 10 then you need to create a Bootable LiveCD for installation
https://help.ubuntu.com/community/BurningIsoHowto
Linux Mint 10 as can most distros. also be run direct from the LiveCD from Boot without touching your Hard Drive
LUg.