RDP is a good sollution, but you should try out the free version of sandboxie... I think it's less of a hassle than running a full RDP. Just open a completely isolated sandbox, drag the exe in the sandbox => completely isolated process...

You can make 1 sandbox for all your altcoin wallets, or use the same sandbox for all... If, after a while, you should trust the exe, you can "recover" the config files to your harddisk and run the exe out of the sandbox...