Vince Young will be the #1 pick in the NFL draft. You can take it to the bank. In fact, does anyone know of a betting site that's taking odds on that bet? If you do, let me know, because I want to bet on Young. Simply put, the Texans can't afford NOT to take him. Even if all their scouts think Bush has a higher "grade" than Young, the cost-benefit analysis overwhelmingly favors Young.
For one thing, the moment Young is drafted, the Texans ticket phones will be lit up like Christmas trees. The Texans need butts in seats, and as exciting as Bush is, he can't draw in Houston like VY.
For another, the pressure to win immediately with a non-VY pick would be tremendous, such that anything short of the playoffs would doom the final analysis to "bad pick," no matter how well the player did. What's the downside of drafting Young? If he doesn't pan out, it's not like you didn't give the fans what they wanted. What's the downside of drafting Bush? If he doesn't work out, you'll forever hear about why you should have drafted Vince Young.
This one's not close. The Texans don't have a choice. Vince Young will be the first pick in the draft. If he's not, you'll know the Texans traded their pick.