Re: background music, a mild narrator and the ability to pay attention

How much listening to a CD interferes with other tasks such as typing or 
reading depends on several things: how carefully they are listening, what 
kind of music they are listening to, how much effort is needed to carry 
out the main task.  Also, people differ.  Some are more distractable than 
others.

From a scientific standpoint, almost anything one does (even something 
passive like listening to background music) interferes at least a little 
with almost anything else one is doing.  Even practicing the tasks, 
separately or in combination, doesn't entirely eliminate this 
interference.  

From a practical standpoint, people's ability to "multitask" varies a 
great deal.  For instance, certain parts of a task may be more demanding 
(less tolerant of having other tasks ongoing) than others.  E.g., reading 
may become more demanding if the material becomes difficult to understand.

So there's no simple or general answer to your question.  The best thing 
is to try doing tasks together, then do them apart.  If it isn't obvious 
to you that combining the tasks impairs your performance, you may want to 
come up with some way of measuring your performance (e.g. how long does it 
take to copy-type a couple of paragraphs with music playing vs. how long 
does it take you with no music).  Good luck!