Once you've found a newsgroup you like and you know you'll want to use it again, you can make it easy to find by subscribing to it. You can subscribe to as many newsgroups as you want. It's easy to view this collection of favorite discussion groups because each time you start Netscape News it displays only subscribed groups. A subscribed group has a check mark in the box next to it.
In Free Agent, which I think is the best-organized news reader program, it's even easier. You just click the bar at the top of the Groups pane, and it toggles between displaying Subscribed, New, and All.
To consider subscribing to groups, you first must be able to see them, so you must tell Netscape Mail to display all newsgroups. For more information see Displaying all Newsgroups.
By the way, "subscribing" actually is a poor choice of a word to describe what you're doing here. It implies you're sending a message off to the person controlling the newsgroup and saying you want to become an official member. But you're not sendng information to anyone or even doing anything at all on the Internet. All you're really doing is adding a newsgroup to your news reader program's list of your preferred groups. It's the same idea as "Favorites" or "Bookmarks" in Web browsers.
If you unsubscribe to a group, it isn't visible the next time you start Netscape News (until you set Netscape News to display all groups, not just subscribed groups).
Main Newsgroup/Usenet Page
Main FAQ Page
Main Internet Primer Page
Bob Fahey's Home Page