The required 10.6 fonts and their respective libraries are found in
Apple Knowledge base article 5154. I don't know for sure about 10.6.8 but in earlier versions moving or deleting one of the fonts in /System/Library/Fonts could make the system unbootable or it could have deleterious effects on readability. Since you have been moving fonts around you might want to verify the location of your system fonts with this list.
Just as a reminder the various Font folders and their use is described in
Apple Knowledge Base article HT2435.
