Yes, when using Express Rip to copy a cd to your computer you can select the output format (and output folder) - and that may well be all you need.
Switch, on the other hand, can be used to convert audio files that are already stored on your drive(s) to other formats.
Here are some examples of how I use Switch.
I do a lot of field recording of local music, and always record the files as .wav files (16/44100.) Many bands have a Live Music collection on archive.org. The Live Music Archive requires files to be uploaded in .flac format,
so I use Switch to convert my .wav files to .flac for this purpose. Sometimes I want to share the tracks with the band (maybe to check setlist or whatnot) via dropbox, and I will use Switch to convert my .wav files to .mp3 format to create and offer smaller file sizes that are quicker to download.
There are many uses/applications for Switch. Hope this helps - sorry for being a smart aleck.
- Dan