2) transmission fluid flush is recommended if you haven't done transmission fluid change regularly. Otherwise you'd be mixing really old fluid with new fluid.
3) I believe the idle valve is on top of your throttle body. It has an electrical connector attached to it. Clean it only if you have idle problems.. otherwise just spray carb cleaner into your intake plenum through the throttle body. (Correct me toysrme
)
Also try seafoam!