Linux Firewall on out of date hardware: kernel 2.2

bogus writes: “An old PC can be the ideal platform to realize a network firewall based
on Linux. The system configuration needs a bit of attention but it’s not
a difficult task to fulfill. The only doubt concerns which kernel version
better suits our needs. The 2.2 version is said to be less memory consuming,
but has a less solid filesystem and lacks other recent features.
What’s the right choice then?

An old PC can be the ideal platform to realize a network firewall based
on Linux. The system configuration needs a bit of attention but it’s not
a difficult task to fulfill. The only doubt concerns which kernel version
better suits our needs. The 2.2 version is said to be less memory consuming,
but has a less solid filesystem and lacks other recent features.
What’s the right choice then?
http://www.portazero.info/modules.php?name=Section s&sop=viewarticle&artid=41“