2000 GMC Yukon Denali headlight problem

I was trying to replace the headlight bulb on my Denali and as I was pulling out the screws to loosen the headlight, only one would come out. The second screw turns but won't come loose to be pulled out. Any help on this problem? I don't want yo force it out and cause more damage.

Is your headlight not like the one shown in this video?
http://www.youtube.com/watch?v=4dsoNWsULDs