Hard drives generally should not make any noises beyond a "whirring" sound. It is likely that this means your hard drive has either a motor failure of some sort, or a head crash. In either scenario it is probably best to go ahead and replace your hard drive. Steps for replacing the hard drive can be found here.

If your screen is cracked, unfortunately you probably have to replace the screen. Luckily removing the screen and installing a new one is pretty simple. Check Dell's site for the repair guide.

After several years many batteries slowly lose their ability to hold a charge. Most likely it is easy to fix this simply by buying a new battery and replacing the old one. In the mean time, turning down the screen brightness and keeping the number of running programs to a minimum should help make the most of your batteries potential.