Oh yeah, pretty much every week of this season (except this week of course). Don't take that the wrong way but seriously, when you're coming from 4-12, and then 5-11 and trying to move up in the world I think that they're pretty much all big games. I'm sure the Jags feel similar to this.
This season we want to beat the Titans and Colts (One game down, three more of those to go) because we've yet to do that. Those games are obviously big games because you measure your improvement by them. At the very same time we want to at least win one against the Jaguars. That's important because on your way as you improve you want to at least keep pace with the other improving team. Then of course every team on the schedule with a winning record is another opportunity to demonstrate that we "belong" among the good teams.
So yeah, this season is full of big games for the Texans (just like it is for the Jaguars I don't doubt).
A wise man once said "...well at this point it's all been hashed out and you either see it or don't. Hoping for a win next week" - HTown2ATX