Is that any reason to create two threads?
CDA is the filename extension for a raw PCM that forms a standard audio cd music track.
You can rip these tracks with any cdripper software. EAC or CDex will do this for you. Both freeware.
Karaoke CD's have additional information stored in the subs (not as part of the data). You will need some form of special karaoke / cd extra player software to retrieve this information, as it's not directly accessible by standard pc software.