The following are the recommended toolset for getting yourself online, your files ripped and shared, and transferring any mp3s you might capture to CD-ROM.

Client:
DC++ - the preferred client.

MP3 Encoding:
Fraunhofer MP3 Professional - not free, but the best.

Ripping CDs:
CDex - ripper and format converter.
Audiograbber - ripper good with external codecs.

Security:
Kerio - free firewall.
ZoneAlarm - free firewall.

Edit and Burn CDs:
Nero - burn CDs.
Audition - edit soundfiles.

MP3 file ID tags:
mp3ext - file info editor.
mp3tag - universal tag editor