How to block?

In my house there is a Linux computer working as a router and a small
network of 3 Win98 SE machines.

Everything works just fun.

But I want to block just one particular machine from chat usage. I have
tried to redirect
URL address of the chat site to local host by editing hosts file, but it did
not work.

What shall I do on that particular machine? User is not very familiar with
computers, but
intelligent enough to exchange cables and reaarnge TCP/IP settings
(actually, to ask for IP
number via DHCP from the provider), but is not familiar in networking, so
....

Do you think, that adding host.deny file will solve the problem ?

Any comments highly appreciated.

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Wladek
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Sprzedawaj mydlo. Per saldo wiecej i pewniej zarobisz
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