Iori is correct, unless you're absolutely sure you know what you're doing, try to avoid giving advice when it involves important files. That said, people should be aware that any help given here is purely by volunteers and whatever they do to their computers is their own choice.
We are also not here to debate the politics behind Microsoft's decisions as to what it does to its software (not in this thread anyway).
KCjoker, information on setting up the SP2 firewall with DCC and IdentD can be found at
www.mirc.org/xpdccsp2 - please remember, mIRC is not a file trading program and is not there purely for "downloading". IRC means Internet Relay
Chat.
Regards,