your post would probably be best addressed in the tech forum...I can tell you however, that they will advise you not to use your home theatre system as it is not designed for live vocals. you would be best to purchase a small pa system for that purpose instead of putting your home theatre speakers at risk of damage.
as to the ripping audiograbber is a free ripper with the capacity to rip cdgs to any one of three or four different options...bin files (to burn to disc) wav + g, compressed + g and one other that elludes me at present.
You may wish to download audacity which is a free record and edit prog. If your wife is that keen, that would be the next step in the process, then she can keep a record of her improvement as she progresses.
As far as the more technical side of things, I will leave you to the experts
good luck and welcome