I really enjoy Monica's. It is a fun atmosphere and good food--good prices. They used to have buy 1/get 1 free dinner entrées once a week (Tuesday?) They have live entertainment some nights and also drink specials certain nights. They have some lighter fare too (for Mexican), which is nice.
As Brian pointed it, its a great place for lunch if you work downtown. Its a quick drive and they are generally good about getting you in a out quickly. Complimentary valet too.