FreeRIP is a CD ripper, thus it is a software that can convert music CD to audio files (like MP3, WMA, WAV, Ogg Vorbis or FLAC). This operation is known as "cd ripping", that's why to access audio CD to OGG Vorbis converter mode, you have to run FreeRIP and select View->Ripper menu option.
Once you are in CD Ripper mode, put the Audio CD in your PC CD drive, wait for about 10 seconds to let it spin up, and then click on the File->Refresh CD menu option.
Then select the tracks you want to convert to Ogg Vorbis and select, from the Rip menu the right option in order to convert them. Example: if you want to convert your cd to Ogg audio tracks, simply select Rip->Rip Selected Tracks to Ogg Vorbis... menu option.