Hi Margaret,
Sorry for my delay in replying, but your email to me ended up in my Spam. To get help it is best to hold the conversation in this (Brennan) forum space. Then everyone can get together to help you.
I note that you have a Baby Brennan, (I do not have one of these so others will be able to advise you better). However, have you looked at and tried to follow these instructions.
To load your music (sorry if you have done this, but it is always worth asking if people know about these web based instruction pages)
I am also puzzled by what you said here "it recognises that the drive is attached, but won't let me insert the CD".
Do you mean that you simply cant get the CD into the reader physically? if so then there is a issue with the CD reader.
One of the first things I think you should do (looking at the menu system in the above link) is to do a "Web Upgrade" then a "Scan Disk".
If these do not help, I think it best to leave it to other members of this Forum to advise you what to do further.
Fred