Audacity is absolutely fantastic for hassle free audio recording of all sorts.
It is totally free and open source.
I've already used it to make great music recordings and grab audio from the net.
You just plug your mic (or whatever) in and go.
You can vary the quality of the recording quite simply, and this will reduce the amount of space the files will take.
You will need to install a small file to allow you to create MP3s, but this is explained the first time you will attempt to do so, and is very very easy.