PIX Firewall?

I manage a small business network of about 13 computers. We use wireless Internet from a local provider. 2 computers are at this building.

We then transmit the Internet to a nearby building wirelessly using an wireless access point. The 11 computers at this second building all receive their Internet through CAT 5 from switches wired to the access point.

There is no data transfer or networking between the buildings. All the computers access the Internet and use email.

I would like to set up a hardware firewall at the first building. Would a PIX firewall be a good choice? What model? Can anyone give me advice on this?

Thanks!