iPhone 4S crashes and now does not reset

[applelondon]

I am in desperate need of help. Last week, my iPhone 4S started crashing the apps I was using. Whenever I am in an app, e.g. mail, it does not open but crashes to the homescreen. I did a reset, did not lose anything but the wallpaper which I tried to set it up again but it does not want to set the photo as wallpaper. Yesterday, the phone was acting crazy so I tried to do a reset again but this time, the reset keeps going back to the beginning after I have completed the reset. I am unable to backup using iCloud as during the reset, backup to iCloud failed. Should I do a backup from iTunes using my Mac laptop first and if that fails, go to an Apple store? Does anyone know if this will help instead of me going into an Apple store?