Re: Virtual OS\'s for web testing, any advice pleas
As others already suggested you can try VMWare or VirtualBox. Other than than MS Hyper-V also available among other products.
I think VMWare has the largest market share at the moment, and it is rich in functionality. If you want to try out, there are two products from VMWare that are free. Look for VMWare ESXi or VMVare Server. They are the free products. VMWare ESXi is a server, where you do not need another OS to install it and access the virtual machines from another machine remotely. VMWare server is installed on another OS such as Windows or Linux, and you can access the virtual machines from the same machine where server is installed.
VIrtualBox from Sun is a free product, and it is also installed on top of another operating system. I believe the version they released last November includes an API too.
If you have MS 2k8r2 license, it comes with Hyper-V. This can be installed on 2k8r2 server, or like VM ESxi, by itself.
I am not sure about running MAC OS without using a MAC since the EULA prohibits running it on any other hardware than Apple. You may need to have a MAC for that.