If you don't have vIRC, you can download the freeware from: visualirc.net.
EDIT: Wrote the above in a hurry, and now I have a little more time. Further for beginners ... once you've loaded and opened the vIRC software, use the "configuration" button at the top to enter your "initial set up" (user nickname, ident, etc.). Make sure the default server is irc.dal.net
Once you've done that, exit "configuration" and click on the "server list" icon next to it ... At this point I scream for help ... some of my settings appear to have disappeared ... I have an idea I should be in DALnet, but keep getting told that *** Cannot change nickname while gagged on #hedgehog when I try to join #hedgehog ... help??!!! Okay, all that was worked around ... make sure you're in the DALnet server.
Now click on the "Start" icon at the top to begin (at which point you should see a window up top appear showing irc.dal.net:6667. Manually retype to this if that's not what's displaying.
Then click on the "Connect" icon at the top. After a moment you should see a screen full of welcome information. Once that has appeared, type join #hedgehog in the text box at the bottom and you should be in (some people may have to type /join #hedgehog instead
If you run into any difficulties, I'll be monitoring this LJ entry, so use "reply" to scream for help and we'll see what we can do to get you in (provided I can get in, of course). :-)