Hi
Installing windows or any other OSs in VMware workstation is not dual boot and vmware create a series of file like .VMDK .nvram and etc , and install os that you want in vmdk so all you see is files. it doesn't touch your hard plattern or cylander if you mean that.
and about your question about how many os can vmware workstation 9 can run its depends on your hardware and RAM and how much resources you want to give to your VMs change.
let me know if you need anything else
Armin Lavaee
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