My question is about lingual frenectomy (laser). I am having problems with my tongue when kissing. How much does this usually lengthen the tongue?

Consult needed. See how far your tongue sticks out now. If it's about 2", then you may not get much added length with a frenectomy. If it's an inch or less there is more of a possibility. These things vary from individual to individual. The need for a lingual frenectomy would be apparent to a dentist who is familiar with normal anatomy. Have a consult to determine whether or not it's advisable in your case.
It depends. Sometimes a frenectomy will make a huge difference in your ability to move and extend your tongue. This will depend on where the attached tissue is on the tongue. Laser surgery is a great way to release this excessive tissue attachment. Healing is usually fast.