What server software/OS should/could I use?

Hi All. I'm posting this in a few forums because I'm not sure where it should go. I'm looking for a server operating system (or software) to manage a network of ~20 computers (all running Win 7 Ultimate) in a computer lab at a middle school. The labs users consist primarily of middle school students, and the teacher has his own computer at the front of the class. I'd like the teacher's computer to be able to remotely control all of the student computers in the following ways:

• Modify and lock various Windows settings such as desktop themes and Windows updates.
• Create/modify user accounts, including resetting of passwords.
• Modify and lock various software settings, e.g. Chrome, Office, Photoshop, antivirus).
• Deploy software to all clients.
• Bulk modify client disk settings, such as add directories, partition drives, and allocate disk space per user.

The network should also allow for relatively easy file sharing capability between all clients, including password protection (but I believe this is more an aspect of the network itself, not the server software).

Some of these are no-brainer server features, while others may be difficult or even impossible. One of the reasons for this post is to ascertain this.

1. Can I do all of this with Windows 7 alone? I don't think so, but would love confirmation.

2. I'm pretty sure Windows Server 2008 can fulfill all of this—but is it the *only* solution?

3. Would the solution require the teacher computer to have a new OS installed, or some software, or both?

4. What operating systems and/or software packages would provide the most comprehensive solution? Free solutions would be more advantageous in my situation.

<div>If you got this far, thanks for reading! Apologies for the long post, and thanks in advance for any help.
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