Hi
You can create a local VMFS datastore on your host using the free space on the local disk. Once you have that you can use the VI client to upload your ISO files to it. Once on the datastore they can be mounted to your virtual machines (configured in the VMs cd rom settings).
This details how to create a datastore for your ISOs, though you may have already done this if you've gotten to the point of creating your VMs.
http://www.vmadmin.co.uk/vmware/35-esxserver/109-esxvmfsdatastore
Thanks
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