Audacity is very popular and used by many. The version you got may not be the "beta" version which the Audacity web site lists as for Windows 7. Audacity: Free Audio Editor and Recorder
However, you need to set Audacity's source device as the USB device so you can "record" from the turntable (one song at a time) and then save that song as a wav file. Repeat this for every song. There are ways to record, for example one complete side and then split it up into individual song files but for someone not familiar with Audacity recording one song at a time is best.