Residential firewall appliance recommendation?

[Alan Dayley]

My father needs a firewall/NAT appliance on his Cox connection.  We have
an old box I attempted to put IPCop on today but it is failing in various
ways (hard drive failure, then not, then CD-ROM not reading, then does,
random).  It is not worth messing with any more, IMO.  (166MHz AMD cpu,
and other oldness)

So, I wanted to find a firewall/NAT router appliance that we could just go
buy and be done with it.  It will have two computers behind it on a Cox
residential broadband connection.  Wireless not needed.

I know the usual choices, I just thought I'd ask the group for opinions on
security and reliability.  Which one(s) are the better of the devices
available?

Alan