No, you cannot export a recorded sound file. You will have to copy and paste it into another sound program and save it.
If you recorded a sound file on a Mac, it may or may not play on a PC.
If you downloaded MP3 sound files, you insert them as QuickTime files so they can be played. These can then be heard on Macs and Windows machines alike.
For more information, please see the help topic "Working with data in container fields".