K3b is great for ripping CDs into various formats. For mp3 ripping via lame, here are optimal settings to use.
In the K3b settings, find and edit the plugin for external encoder. There you should find an entry for mp3 (lame).
Here are my recommended settings to use for -V2 quality:
lame -r -V2 --tt %t --ta %a --tl %m --ty %y --tc %c --tn %n - %f