If I take it as we must be 100% safe, then nothing is safe.
BUT if you want to dump Kazaa, then use this -> Kazaabegone from http://www.spychecker.com/program/kazaagone.html or other sites.
As to other programs and deleting them, beginners shouldn't do this manually and those who know, don't ask very often. This is, in no way meant to slight or upset you, but it's the awful truth. I write it bluntly since the trouble I've seen with people getting into the registry "to clean things up" is rather horrible to see what happens to many.
When I go to run and type regedit, and click the
HKEY_CURRENT_USER and then Software, I noticed that programs i deleted such as Kazaa are still there. Is it safe to delete these items? Where else in the registry will I find deleted programs that have not been cleared from the registry and can I delete them?