Copy and paste this in your url: irc://shardsofdalaya.com
It should open up your IRC client (IE: I use mIRC) automatically
Then type /nick nicknamegoeshere
To join a channel (IE: the default shards channel) type /join #sod or #channelname
It sounds like it is not recognizing your IRC client. Try downloading another IRC program. I use mIRC because it's the most user friendly (in my opinion).
Well it was chatty up until just a bit ago. Perhaps people gave up hope for the server coming back up tonight and decided to go out and experience IRL for a night! Also, there are a lot of sub-channels people join for their guilds etc, so I'm sure it's chatty just not where you can see it.