I use Trillian also. There is a downside to it, though: AOHell doesn't like it, so they keep writing patches to keep Trillian off of the AIM network. So, Trillian writes one to get on…and back and forth. Right now I'm having to use AIM until the next patch comes out. I much prefer Trillian; it's much more stable as a program than AIM and looks much nicer; no annoying ads.
When it comes to ISPs, if I have to use a dialup, I actually prefer local ISPs to the big national ones; the service is better and there are fewer busy signals. I dislike the “amusment park” atmosphere and the fact that they seem to make it purposely difficult to go to the world outside AOL's walls (with the “keyword” nonsense). However, nothing is better than free access to the school's T1