I had CO2 laser just around my eyes about 7 years ago. I love the results as far as the fine lines (completely gone to this day). It did not change pore size at all (some pores were zapped with the CO2 near my eyes).
I would recommend this only for fine lines. My skin was still very firm so I cannot say whether it helps with skin tightening.
The healing process was the worst. The lasered area stayed blistering red on me for three months after the procedure! For the first month, I had to use water mixed with vinegar on the area...just plain water on the area would sting the area. I had to keep makeup on the area for about six months (still pink after three months but not nearly as red).
Seven years later, there is still a pigment difference between the lasered area & the rest of the face (it looks lighter than the rest of my face but not too much lighter...self-tanner on the lighter area helps). It was very painful healing, but the fine lines I had are gone still. I am very glad I had it done!!!