iTunes doesn't restrict burning by other apps.
It includes the GEAR CD writing code (iTunesHelper.exe, I think), nothing more. It doens't make any attempt to restrict what can be burnt by other apps, the only way it enforces its DRM is by refusing to burn stuff itself. And it does that very rarely also, it will let you burn a track an unlimited number of times, only restricting how many times you can burn a given track list without modifying it.
It also starts a service called "iPodService.exe", but it doesn't relate to CD/DVDs at all. And you can kill it in Windows Task Manager if you want to see if it makes any difference.