1. All the gifts given to her from either side of marriage is considered to be her stridhan and hence she alone has exclusive rights over this. Whether you will hand over those to her on mutual consent divorce will depend on terms of settlement between two of you.
2. In mutual divorce the terms of divorce depends on mutual agreement of the parties. There is no law guiding the parties on this. So if you can convince her you need not pay anything.
3. If you are parting ways then bury the past and dissolve the marriage amicably. If she has greed for money without alimony MCD is unlikely to happen,