NginUS has already told you how it is possible using Distributed File System with a Windows Server on the network, which is the best way to do this.
There are some other ways I can think of:
First of all, have you considered using the HomeGroup feature of Windows 7? It was made exactly for the sort of thing you are trying to achieve, although it requires Windows 7 on all the computers you want to use it on. I've not used HomeGroup as I have a domain network, but I think you can use Libraries with it.
Another way is to use Libraries on the client computer. You just add individual network shares to it, and they all appear as one in the resulting virtual folder. The client computer(s) needs to be running Windows 7 for this.
The other way is by using a kludge that I have just thought of, but not tested. You should be able to make a folder somewhere on the server computer and share it. Then make two Junction Points [
mklink /j] pointing to the two movie folders in that folder. The only problem with that is that you will see the two folders contained in the single network share, instead of all the files being shown together, like when using Libraries.
You can also do the same, but on the client computers, using Symbolic Links [
mklink /d], pointing to the remote network shares on the server computer, but this requires it to be done all on the client machines and I cannot see any point in this method.