What was your old Minidisc recorder?
If it was not a Hi-MD--that is, the model number does not have an H in it and there's no Hi-MD logo on the machine--then the recordings were made to be stuck on the disc unless you wanted to re-record them in real time.
That is, until Sony introduced the MZ-RH1. That will upload legacy MD recordings IF you made them yourself--not if you downloaded albums from your computer onto the disc.
They are hard to find now, unfortunately. And people are getting greedy, if Amazon is any guide. The former Minidisc Canada still has the MZ-M200, (same unit, MZ-M200 comes with a dinky Sony mic)
http://pauseplaystop.com/shopdisplayproducts.asp?id=1&cat=MiniDisc+RecordersIf you have a whole lot of MDs, the time you save might be worth it, and you'll be doing a direct digital upload instead of an analog recording.
The MZ-RH1 or MZ-M200 will upload recordings through Sony's barely tolerable SonicStage software onto a PC. Here's the best available version of SonicStage:
http://forums.sonyinsider.com/topic/26171-software-for-your-netmd-or-hi-md-minidisc-playerrecorder/ Once uploaded, you can remove encryption, also with SonicStage--actually with the File Conversion Tool, which will install under the SonicStage group in the PC but runs outside SonicStage. The uploaded files are in Sony's proprietary ATRAC format, but after uploading and decrypting you can convert them to something useful like FLAC or .mp3.
There's a lot of information on that Sony Insider site, formerly minidisc.org. If you do get the RH1, look around there for info or ask for help--a nice bunch of minidisc diehards.