Protecting the enterprise wireless network

Hey all.

We want to implement a separated secure Internet Wireless network which will be used by guests or users from our company in our building.

We will use Access Points, managed switch and Gateway device that you might offer. The Gateway can be also a Linux (open-source) based solution - it is much better for us :)

We are looking for the following features:

1. Only HTTP, HTTPS, SMTP will be permitted, and it will be great if it is also analyzes the protocol, not just blocking a port.

2. QOS - Some kind of traffic shaping to balance the Internet between all users.

3. We want to limit the access from specific time range.

4. Since there is a chance that a User from our company will accidentally connect the LAN cable without disconnecting the Wireless network. Is there any way to block all access between all connected Wireless users? So that an attacker won't be able to access any of the Wireless clients?

Best Regards,
Zeffy.