To launch Parallels Desktop you have two choices. However, version 7 of Parallels includes a security barrier to ensure there is absolutely no risk. There's no need to worry about viruses on your Mac by running Windows in Parallels Desktop - any viruses will be restricted to the virtual environment that Windows operates in and won't affect your Mac in any way. The Transporter feature guides you through the whole setup process, asking you if you'd like to be able to share files between OS X and Windows and use external devices amongst others.
Parallels Desktop will then install Windows in about the same amount of time that it would take to make a fresh install of Windows on a PC. You'll either need a copy of Windows on CD to install it or an ISO image will also suffice.
Setting up Parallels Desktop is a breeze.
