I was able to use an ogg sound file in Huey Apocalypse, after trying mp3 and wav. I had the file in an mp3 and used an on-line mp3 to ogg converter which worked well. So, I don't think getting an ogg in the end is an issue.
I will check the Win sound recorder.
There will be a Hog driver and a C-130 Herky driver talking to each other. I need two or four 'conversations' -- one that starts the ingress to the pickup site, and one on successful completion. One for an abort and one for a damaged C-130 (Hog drivers did not do their job!)
For the Hog driver I plan to have an A-10C running on my second computer while making the voice recording -- that will provide background engine sounds, and have a C-130 flying around in the background for the Herky driver voice recordings. But, it does sound like I could make all the recordings separately and you could mix in the background engine noises. Hee hee, and maybe some explosions... Need some radio static, too -- I wonder if that effect is built in to the Radio Transmission Action in DCS?