I connect my compact cassette deck directly to the line input on a Soundblaster Live! card on an old Pentium PC. This has a lower noise level than the sound card on the motherboard on either my Core 2 dual or iCore PCs. The same card and motherboard in another PC is too noisy to use at all. This noise is a low level hum that can be heard when nothing is playing or on quiet sections. An external USB sound card avoids these problems. http://www.mcmullon.com/reports/importing_audio_video/importing.htm
I use Audacity (free) and Nero to save as wave and MP3 (320 or 192 for lower quality tape) and also then convert to AAC 128 for use on an MP3 player but not all MP3 devices will play AAC iTune files or other formats. If you have the space save as a WAVE file. MP3 at 192kilobit/second will compress to a sixth or tenth. I convert the wave file to 128 kBit/s for use with an MP3 player.
Audacity allows tracks to be cut and saved separately, but as my cassettes are either live or without tracks I have not needed to do this often. You can always do this later if you go back to the original wave file. Don't edit MP3 or iTunes, particularly if heavily compressed at below 192kBit/s.
I use MP3Tag (free) to convert the wave file names to tags. iTunes truncates file names, but the original wave file name is in the title tag. I save this to filename first and then convert track, artist, title of the file name ( Track - artist - title ) to the correct tag. I give the sub-directory the name of the album.