Al is correct that Texas (unlike the other 49 states) has laws in place that effectively prohibit lease-options. However, I disagree with him that they're so one-sided. Still, that's a moot point since you aren't going to be able to structure a deal the way you'd really like.
I do agree with his suggestion to keep renting while you're working on the credit scores and saving up the money for a downpayment.
Hope that helps.