macbook air late 2010 yosemite only 2gb ram have availablity 60 gb but storage about my mac says i have 50 gb movies which i have not and 50 gb apps which i have not. hidden from me in all my files. should i try ma OS Recovery or try Clean My Mac 3 or C-Mac software. runs rough and hot when using or connecting with wifi and external harddrive.. best way to view and erase hidden files.