Xilisoft Sound Recorder

Xilisoft Sound Recorder is a very complete audio recording tool. I don't usually say this, but this application has everything you probably need to record any type of audio on your computer.

There is also a very nice graphical user interface that makes everything very easy.

The application can record any audio that goes through your computer. You can record the microphone input if you want to create voice recordings, or you can use the "What You Hear" input, which will effectively record anything that is played on your computer, I think including your microphone. There is an option to record only VoIP applications like Skype. The recordings can be saved in three different formats: MP3, WAV, and WMA. There are a few quality settings that you can change for each of those formats, including bitrate and frequency and the number of channels.

Xilisoft Sound Recorder has an excellent support for hotkeys. You can use combinations of keys to start a recording, stop it, pause it, and activate monitor recording and spy mode. The trial version of this app limits you to ten recordings, which should be enough to test all of its features.