Should I pay points to lower my interest rate?

No! Not unless you plan on staying in your home and mortgage for a significant amout of time and have extra money to make a significant difference on your rate and payment.  If you plan to stay in the property for five or more years, your monthly savings may be enough to recoup the cost of the discount points that you paid up-front.  However, many circumstances arise that trigger a need for refinance, therefore paying discount points in most cases does not make sense.