When I first got started converting MP3's from CD's, I used a program called MusicMatch, though I am not sure if it is even still around.
I found my main needs were that it had to be able to connect to the internet and search GraceNote or some other database so it could get the artist and song/album info to tag the MP3 file with, and it needed to be fast, as I converted around 500 CD's.
I also found a need for some way to Volume Level MP3's, and for this I used MP3 gain, though I would caution you to make sure to save the log file it creates, cause once you change the DB level of a file, there is no way to know what it was originally set at. I leveled all mine at around 89db if I remember right.
Then, along came Apple Itunes, and it seemed to be able to do most everything I wanted, though I did notice it was somewhat slower converting entire CD's to MP3. I later converted all my MP3's to AAC format (but I also saved the original MP3 files). Doing this cut the size of my collection in half, without any real loss in audio quality. So now I can get twice as many songs on my Ipod as before, and they still sound just as good as they did befoe. Converting my entire MP3 collection to AAC format took something like 10 hours. If I had it to do over again, I think I might have done the original conversion in AAC, although that limits the files to being used only on Ipods or in Itunes. MP3 is a more widely used format, but AAC has better compression technology. Since all I ever use is the Ipod, AAC would work fine for me.
I tried the Microsoft media player product and was not impressed with it. Music Match and Itunes were both better.
Since going to Itunes, I haven't really kept up with the latest software out there for MP3 files, and I am sure there are new products that would be worth a look.