回答“Why is my hard drive so loud?”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.
回答“What should I do if my screen is cracked?”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.
回答“Why does my battery only last 30 minutes?”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.