As long as the CD still has enough unused space on it, you can add photos.
CD
You can do it yourself if you have the means to upload or scan your photos onto your PC then just copy them onto a disk.
Put the CD in the CD drive of your computer. Assuming it is using a windows operating system, open 'my computer' and double click on the CD drive. You can then click and drag the photos either onto your desktop or into your 'my pictures' folder. You can also right click on the photos and select copy, then right click and paste them into a document or a folder.
To copy a CD that is not a copy you can get a RW CD. This is a CD that can have things copied onto it.
No, as long as you have a CD/DVD drive that can write to discs, then it should work.
You can record photos onto a blank cd-r. Once recorded you can copy it to a folder or pendriver. If your operating system is windows 7 you can modify, delete and move a recorded data, image, audio or both but you must prepare previously the cd-r or cd-rw.
The best way would probably be to get a hardware specialist to download the photos of the main drive of your iMac.
No.
To keep music on a CD, it is already there and you do nothing. To put music onto a CD, you "burn" it to the CD. To copy music from a CD to some other memory location, you "rip" it.
i ain't know
Only if it's labeled CD-RW or CD+RW
You can put the CD files on your computer and then burn it into a blank CD or buy a duplicator which makes copy's of Cd's.