Any protection schemes aside which may throw a monkey wrench into
anything you try to do 'legally' with any newish commercial CDs these
days editing and adding effects/enhancements is fairly straight
forward.

Grab a download of Audacity, it's a FREE, very capable entry level
audio Swiss knife kind of tool which you can use to manipulate most
audio files. It presents your file as a visual waveform which can be
easily edited.

Yes, Audacity can easily fade a song to total silence, change pitch,
tempo, things like that. Eliminating vocals while technically possible
with some pro grade editors if you happen to know some good audio
engineer then yes, you can more or less do it otherwise no way since
by the time you've got the CD or whatever source you're using the
vocal track has been merged into one or more channels which most
always also includes music, there is no longer any vocal track to
delete or separate from whatever music may be present.

If you want a professional one - go with Sony Sound Forge or Adobe Audition
http://www.sonycreativesoftware.com/products/soundforgefamily.asp
http://www.adobe.com/products/audition/?sdid=BDXEY