What role should the Bible play in discussions about sexuality
"Should" implies a systeme of values and beliefs. The role of the Bible depends on which parts of the Bible you accept -- Old Testament, New Testament, both or neither. There may be contradictions within these sources, leaving the readers of choose what they accept.
Problems arise when some people believe their interpretation is the only one that is valid, negatively judging other people who differ in their interpretations as bad or evil.
There are some articles under in the Human Sexuality readings that might be helpful.
See http://www.members.cox.net/dagershaw/index.html
Look among the 400 articles in the Human Sexuality area.
I hope this helps. Thanks for asking.