It depends on what your purpose is. If it's to get access to binaries whether legal or otherwise - oh, sorry, I forgot that there's no such thing as a legal newsgroup download
- your best bet would be to go to a 3rd party news server like Giganews. Most of the internal newsgroups of ISPs are crap for the simple reason is that hosting newsgroups is expensive because of the MASSIVE amount of space and bandwidth that is needed.
Before doing any further searching, however, make sure that your ISP (particularly if you're getting it over cable) doesn't pull any of that draconian "we f**ked up by underestimating the demand for our services so we put in a sh*tty infrastructure and we're going to punish you for our stupidity by unethically putting a monthly data transfer cap on your connection for which you think you're paying unlimited access" limit on bytes transferred per month. You could end up paying far more for your newsgroups than you think if that's the case.
If it's just for basic newsgroup chit-chat, like how we use HTF, most ISPs will have a good amount of newsgroups, but their retention rates might be crap because (again) of the space needed to store those groups.
