[TriLUG] OT: Intrusion Detection for Windows ?

[Maxwell Spangler]

I've got a Windows 2000 system running a legacy app that deals with
credit cards.

In order to meet VISA and MC credit card security rules, I have to do
some commonsense things like install firewalls on my net connections,
install anti-virus software, have trusted versions of the legacy app
running, etc.

But it also requires intrusion detection software.  I'm looking for
something about as simple in easy of configuration and low cost as your
typical anti-virus software.  Can anyone recommend something that would
get the job done without much fuss?

ps. I don't want to belittle the need for IDS and related technologies,
but the rest of the details of this site simply don't merit the kind of
attention that an ecommerce website might warrant.

Thanks,