What is safe to delete?

I run a PC with win.7 and i noticed that I have a lot of files that I would like to delete. Every time I upgrade to a new adobe or ccleaner I have the older version. if I only keep the newest and delete the older version will I lose anything I need?

 

No you won't lose anything just delete the older versions !

 

P.S only delete the ones you see in Control Panel's Install/Uninstall programs !

 

Do you mean the downloaded installer, or the installed program?

Adobe (Reader?) always uninstalls the previous version before installing a new one. Sometimes (especially when skipping a version, e.g. upgrading from 8.x to 10.x) this does not fully work. So I always manually uninstall before upgrading a major version.

CCleaner always installs into the same folder, so you will not have an older version of the installed program. Best not to uninstall, but install over the existing version; this way all your settings are kept.