Using Pidgin for IRC

pidgin is quite a good irc client.

Once you have downloaded and installed pidgin:

• Accounts > Manage Accounts
• Add...
• Protocol: IRC
• Username: your preferred nickname (please use your real name)
• Server: your irc server, eg irc.freenode.org
• Password - leave blank
• Add
• Close (the "Accounts" window)

Back in the main pidgin window:

• Buddies > Join A Chat...
• Account: the one you just created
• Channel: #favouriteroom, eg #pidgin
  
• Password - leave blank
• Join

In the new chat window for the chatroom:

• Conversation > Add...
• Tick "Autojoin when account connects."
• Tick "Remain in chat after window is closed."
• Leave everything else as defaults
• Add

Now when pidgin launches you will have "#favouriteroom" in your buddy list, and you can double click to open the chatroom.

You may also want to make pidgin start when windows starts;

From the main window:

• Tools > Plugins
• Tick "Windows Pidgin Options"
• Configure Plugin
• Tick "Start Pidgin on Windows startup"
• Close
• Close (plugin window)

I also recommend enabling the Markerline plugin to help see what is new in the channel.