Oh LOL.
VGA is analog, and has six wires for color (red signal, red ground, ditto each for blue and green). It's not /exactly/ serial (serial as I understand it is inherently digital, which VGA is *ahem* very much not) but the paradigm sort of fits. RGBTTL is parallel. You have one wire per bit of color. So that's 18 wires. Plus your sync lines... which may or may not match VGA signal standards, I'm not sure.
If you actually manage to figure out how to get that hooked up correclty, let me know ;)
(Hint, it's doable, but you need additional components. There's a cheap way, and there's an easy way, and they are two *very* different ways...)
Much easier suggestion: get a small LCD. *ANY* small LCD. Like a five or seven inch display at the largest. Raw panel, no driver board. Get the datasheet and a compatible connector. (If you source from eBay this is very easy; those are almost all commodity displays with available datasheets.) If it's a SMALL DISPLAY it *will* be RGBTTL, 90%+ of the time (I've seen one exception to this ever and it was in an off-brand portable DVD player). Wire it up. Wire it to the card connector. Add power. If you get a screen that works, you've done it right.