Mr. Mangal, You seem to be a diiferent person and not connected with Ms. Vidya. Propriety requires that you should make your query seperately. Nevethless, my answeers to your queriwes are as under:
1 and 2: Please see the difference between will and gift explained by Shri Vishnu. If u want that ur son should get the property immediately, then gift is the best way. But gift deed attracts stmp duty and registration chares based on the current market vlue of the property. Stamp duty differs from State to State, but at a concessional rate. In Mhazrashtra it is 2% if the gift is made to blood relations such as son, daughter etc..
3. Registration of will is optional, not compulsory. It can be registered at the place where it is executed. But pl note if at a later date u want to change the will, you will have to execute and registter a codicil (amending document).
4. The son to whom u bequeath the property under the will, will get the title to the property automatically on ur death. But the will requires to be probated in a court of law. For details pl consult ur Advocate.
5. Settlement deed is different. Generally it is executed where a person wants to settle his properties with immediate effect amongst his family memebrs or for those for whom he wants to provide or for any religious or charitable purposes. While will takes effect on the death of the person making the will, settlement comes into force immediately on its execution and registration. It attracts heavy stamp duty.