ummm...
either im confused or your question doesn't make sense--
If you buy an audio cd, then you can sample off of the cd just like you could a record or whatever.
If you buy a cd that doesn't have audio, but has, for instance .wav files, then you can play those on your pc and then sample off of the pc.''
However, all mpc2000 load .wav files, so just copy the samples you want from the cd rom to a floppy and load them on to your mpc.
If you buy a cd that doesn't have audio or .wav files, but has files in someother format, you won't be able to use them at all unless you use a translation program like chickensys.