Q: Novice needs to convert SoundTrack files to...?

I received a group of old SoundTrack Pro files that are narration only.

One day (...who knows when ) I am going to use this files to narrate some pictures/video.

Since I won't be using SoundTrack Pro to do that (I don't know how to use SoundTrack Pro), I am wondering what type of file I should convert these to and how, so they are audio files that I can flexibility use in the future.

Some of the audio is very very faint, and I want to make sure not to lose the quiet sounds when I convert the files. Not sure if I should be trying to "enhance" them so not to lose the sound first in SoundTrack Pro, or if I can move over to another file type and that will be fine.

Thank you everyone!