MAC OS X RESTORE G4

I was having problems with my browser SAFARI, so I did an update;
after the update. SAFARI was no longer the default browser it was IE
for MAC. For every page I opened.
After that I used the installation CD’s to get everything back to
normal. However I lost all my pictures over 3000, and also my music
from iTunes over 4000 songs. Now I don’t know how to bring all of
my old files and pictures?
Question:
Can I do a restore on my iMac?
Or how can I retrive what I had before? In regards to at least my PICS
and Music?
Please give me a hand…
norman.verbel@att.net