First I will comment on the virtual machine question that I overlooked. I virtual machine is a virtual computer with virtual hardware that you can run from within an operating system link a general application, some popular personal virtualization software are virtualbox, virtualpc, kvm. With this solution you can launch the windows based virtual host from within you Linux based OS, unless you chose otherwise the virtual machine is restricted from communicating with the primary OS data and hardware. Virtualbox has what is called a snapshot tool that allows you to save a virtual machine at a specific time and revert back to it when you need, in this was you can install a virtual machine with windows and set a snapshot from the initial install that can be reverted if an infection occurs.
#d acceleration is used in video cards for things such as transparency effects and some video games, unfortunately the only was to find out if something needs it is when you gen an error message, however at least in virtuabox you can enable a guest machine to use 3d acceleration on specific hardware.
ClamAv is used as the core for many of the commercial AV software because it is free, the protection is quite good and generally better than norton or mcafee which I have found to both be jokes. You can use ClamAV as a base in the Linux OS to catch most issues and still install a commercial AV product in the windows installation to accent your protection. I have never used bitdefender of Kaspersky, but for my friend and family with windows I always recommend Antivir because it is outperformed every other AV I have attempted to use for cleanup.