Ok, if you are both qualifying together, you should have an equally great score or it may raise the rate and hurt him.
Assuming you both have similiar scores and are putting 20% down, you should qualify for a great interest rate. If you do a 15 year note, the rate will be lower than if you do a 30 year note. As far as buying a lower rate with points, I would advise against it. There are times where there will be benefit if the points are low for a large change in interest rate and you plan on occupying for many years, but usually the break even time is years.
Rates are so low right now and with 20% down and mid-700 scores, you should both be in great shape for low to mid 3% rates. Good Luck.