Thanks for the replies guys, i was trying different methods to solve this problem .. i ended up blowing one of two Arduino Uno that i have 
i got a 12v power adapter and hooked it to a power socket. after i saw the smoke coming out of the board i instantly unplugged it. the oonly reason i did that is because i assumed the LCD needs more power. the board was damaged , even though when i plug it to my computer with the USB cable it turns on, but i cannot upload anything to it.
i tried the LCD on the other board to see if working or not ... the back light works, i can even turn up and down the contrast .. but no TEXT all. i tried different codes .. but nothing .. only thing i can see is one box blinking when i upload the Blink example from the arduino software.
I'm going to order a new LCDsss lol, and another back up board. Which board is the best ? i have Uno already but i need another advanced one
Anyways i really think that the problem that i had was either voltage .. like not enough power, or pin conflic
Thank you again guys, and if you know a way to actually check if the LCD is bad .. please let me know how. Is it possible to check it with the multimeter ?
thanks guys 
Barry, AU