The fantasy advice for this game is fairly easy for those soldiering on in the playoffs or desperately wanting to be the best in the consolation brackets.
The Texans have the league's 29th-ranked defense. They're allowing 378.4 yards and 27.3 points per game.
The Titans are 20th allowing 364.9 yards and 20.4 points per game.
DVOA-wise, the Texans give a significant bump to opposing offenses while the Titans aren't more than a speed bump to opposing offenses.
All that said, I would start Matt Schaub, Andre Johnson, Arian Foster, Owen Daniels, Neil Rackers, Kenny Britt, Rob Bironas, and Chris Johnson. Most of these were either drafted in the first two rounds, have been pleasant sleepers, or have good chances to score points against low-rated defenses.
If you're succeeding, you're likely not starting anyone else from these teams. If you're looking for some late-season magic then I'll throw out Kerry Collins and Jacoby Jones as sleepers.
Collins is a decent NFL quarterback, so there could be points against the Texans defense (who has allowed 2-plus TD passes in 11 of 13 games) if you're in a pinch for a quarterback. Jones has caught touchdowns in consecutive games and sees an average of five targets per game, so there could be something if you're looking at taking a chance.