There is no way that you should be consuming 60 Gbytes of disk space for a "plain vanilla" Windows 7 installation where you test websites with IE and Chrome. The problem is that your virtual machines are growing from temporary files. I doubt that you can get a new Windows 10 installation down to 4 Gbytes, but you can do much better than 60 Gbytes.
Before you do anything, shutdown your virtual machine(s) and make a full backup to an external drive.
Next, cleanup unnecessary files on your Windows virtual machines. Here are some handy links that I found with a quick web search. The second link offers more "radical" suggestions - use common sense, please!
Reclaim Disk Space By Deleting Old Update Files In Windows 7 | Liberian Geek
This one offers more radical suggestions. Do not follow them blindly:
6 Ways to Free Up Hard Drive Space Used by Windows System Files
In addition, you may want to delete caches, etc. that your browsers accumulated (IE, Chrome).
Once you are done saving space in your Windows virtual machine, you can defragment the drive (in Windows), shutdown the virtual machine, delete snapshots (make sure you can afford to lose them!), and then recover extra disk space. Here are the official VMware instructions for shrinking an overgrown virtual machine:
VMware KB: Defragmenting, shrinking, and cleaning up VMware Fusion virtual machine disks
Good luck!
