Came across this problem today and couldn’t find any Google hits that helped me. Finally hit upon a solution.
VMware tools requires the guest to have a CD drive. In my case the physical host doesn’t have a CD drive, and I had no need to mount any CDs in the guest, so while creating the guest I removed the CD drive. No CD drive => no place for VMware to insert the CD. But rather than complain about it, it simply grays out the option.
So that’s it. Enable the CD drive and you will be able to install VMware tools! Hope this helps.