Obviously, things will change over time, but as of yesterday, the following advice applies.
Audacity is very popular Open Source (i.e. - free of charge) audio editor (and recorder) software. It took some research and a little effort, but I got it to work on Windows 7, with a first time clean install.
At the moment, the trick is to use the Nightly Build. You can find it on this page:
http://wiki.audacityteam.org/index.php? ... s_Binaries
Under the Windows Binaries section, click on Unicode Release.
Unfortunately, that only gives you a Zip file. Extract it to C:\Program Files\Audacity (C:\Program Files (x86)\Audacity if you are using the 64-bit version of Win7) and then create a shortcut to "C:\Program Files\Audacity\audacity.exe" on your Desktop, Start menu or System Tray so that you can actually start up Audacity the next time you need it.
At the moment, the Nightly Build is 1.3.10. The so-called Beta version is 1.3.9, and it appears to work until you try to save some settings from a non-Admin user ID, then it blows up on a permissions issue.
The "Production Version" is currently 1.2.6, and it is strongly NOT recommended. It turns out that it was written for Windows 98!
Hard to say when it will happen, but the Audacity Project is working on Version 2, which will probably be 1.3.10, 1.3.11 or 1.3.12, whichever proves to be stable, and will fully support Windows 7.