If the laptop was switched on when it fell then you are going to need a new hard drive (with the exception of laptops that employ G-Force detection, such as IBM Thinkpads and Fujitsu-Siemen's Lifebooks).
Hard drives are built to withstand quite a high impact (up to 350G when not in motion - ie. powered off). However, when operating, the impact that can withstand is about 3-4G - which is going to be exceeded by any drop of more than about 5 inches.
The problems you are getting will be, in the first instance, because of hard drive damage. Repair wise, you will need to replace the hard drive (not expensive and does not generally require a technician). You will need restore disks to reinstall the operating system on the new hard drive.
With regards to the back-light on the screen, it is actually very unlikely it is the back-light that has gone. The component that actually goes is usually (and we are talking 99 out of 100 cases) is the 'inverter'. Fortunately the inverter is actually quite inexpensive, and is also straight forward to replace. So if you do take the laptop to be repaired for that fault - make sure not to let the engineer/shop assistant tell you the back light has gone because they will be charging a whole lot more to replace that than the inverter.
Even if you would prefer to buy a new laptop, it would be worth replacing the hard drive to be able to sell the laptop.