One button cleanup in NSW 2008

I'm confused.  When I run "One Button Cleanup" in System Works 2008, it finds a number of temp files.  However, it doesn't remove them but I have the option of ignoring them for future cleanups.  I don't want to ignore them, I want to get rid of them--unless they are important.  Can I just go in and delete them from my computer?  Do I need these files?  And if not, why doesn't Cleanup delete them? 

Thanks for any help in clarifying this.