I'm a Mac user, so I can't investigate this thoroughly, but I also have seen evidence that the Windows version of WMP sometimes adds DRM to files you rip from a CD yourself. I don't know if this is definitely true, but I'm pretty sure I hate WMP, regardless.
I hope I don't get tomatoes thrown at me here if I suggest iTunes - there is a Windows version, after all, and it works pretty well as a song ripper. It's also great for managing podcasts and other tasks, but don't use the iTMS if you want to play the songs on a PocketPC.