I need to setup a free hotspot at a local business for customers to access. I'm thinking very simple: DSL, Wireless router. However; I need to do a few things: no porn or other sites that some term as bad. I will probably have one business computer that needs to share this same access. Not sure yet if this computer will be operating via wifi or wired.
My questions:
1.) How do I filter the "no-no" sites from access? I looked at OpenDNS, but very expensive for a business.
2.) How do I keep free wifi users from accessing my business traffic?

Sorry if these questions are too basic.