I have been having slow performance and software issues. Several software are either moving soooooooo slow or i have to restart the computer because it won't function. I am thinking about just reinstalling OS X, but at the same time, I get worried with all the music and photo files I have...how can I save them in terms of leaving them on there? backing up? will that assure that they will remain? and how do u back up files?

Please let me know who ever has done this. I appreciate any advice. Thank you so much.