For most users, the needs of audio editing software fall somewhere inbetween Sound Recorder and Adobe Audition. Thankfully you can do much better than Sound Recorder, but without any additional cost, as seen in the free and open-source, Audacity.
Available on virtually all platforms, Audacity is the hugely popular audio eeditor intially released in 2000. It features a substantial list of features, including noise removal, support of several audio formats and qualities, change tempo without altering pitch, among others.
As a general-purpose tool, it will cover most needs quickly and easily.