CuteChat 1.0 is the new IRC client for Windows 95 and NT. It's the most technically advanced IRC client (featuring full C-like scripting language, plug-ins, etc. as well as the standard features you see in mIRC and Pirch) but it's also very easy for new users because it provides a full tutorial.
Jump to the CuteChat web site for more information, or go directly to the download page. (If those URLs fail, try http://subnet.virtual-pc.com/ma407651/Forge/CuteChat/.)
CuteChat is shareware (like the two other major Windows clients) but is fully functional.