Recording audio is fairly simple -- the difference between the old Windows Sound Recorder & couple hundred dollar software isn't the part where audio's written to disk. SO just about any audio recording app will do -- I like wavosaur for it's plugin support etc., but there are loads of simpler, easier to use apps without any editing functions.
THE problem is that the drivers for audio hardware [motherboard audio chipset or card or USB device] frequently don't allow you to record speaker out -- what creative labs products label What You Hear. If/when that the case, Google. Sometimes there's another driver that will work, say from another manufacturer using the same components. Sometimes it just takes a simple registry edit.
If there's no cure apparent when you Google with your make/model system, some people hot wire the connections, running a jumper between speaker/headphone out to mic/line-in. You can also use a headphone splitter with volume control to try & tailor levels. There are also virtual sound card drivers -- most of the one's I've seen are bundled with audio apps, usually out of China, but those are just what I've seen, not necessarily a reflection of what's out there. There are also ASIO drivers, sometimes hardware specific, or if those are unavailable, ASIO4ALL -- however the software that will use ASIO is more limited.