LCD lights up but shows no text
From provided picture it is visible that your display is not alphanumeric display (with most popular HD44780 driver). It is a graphical display (most popular: KS0107 or KS0108 or ST7920). You can count horizontal pixels and vertical ones in the picture to confirm its resolution.
Without too many problems you can drive it with your Arduino. Try to use some of 128x64 Arduino libraries. Also, check the rear of the display for any part number to confirm the driver (search in google).
 Good luck!