Mac Help! Please!

Help!!! I am currently looking for anyone that might be able to help me with computer clean up.  I've kind of gotten in over my head in photos and movies on my computer and my Iphone.  I am always so worried about losing my pictures and movies that I save them in a million places and I am so afraid to delete them! So I currently can't really do anything on my Iphone because I have so many movies on it, and I have tried burning DVD's of my iphone movies, but for some reason some are missing.  We have so many different back up devices that we bought, more memory for our computer, and I am just not sure what to do with it all, or how to find out that I am really saving things there.  I am pretty clueless about Iphoto, IDVD, Imovie, Itunes, etc. and although I attempt to use all of them and can get some things done, I know there has got to be an easier/better way! 

Anyone good with this stuff that could possibly give me some quick tips so that I would be able to use my phone this weekend?? Or for longterm know of anyone/anywhere I can take my computer to to get help with this all. I don't really want to just drop my computer off to have someone do it for me, I really was hoping to kind of sit/talk with someone to figure out how to do it all on my own.