vga screen

I’m trying to switch from AV to VGA but the only thing i get is a blue screen. I tried to check if the wires were connected correctly, and it looks like they are. But when the wires are connected to the wii and the display driver, the tester tells me that all the RGB wires are shorted to the GND...

As the title makes obvious, i need a 6 to 6.2 inch (preferably good quality) screen for my upcoming first wii portable. so, that's the size i'm going for, but i need that kind of connection, and hopefully, not too expensive, ($50 or less hopefully). Any help is appreciated, Thanks!