Marriage registration

1. Can a Registrar from Barasat or Kharagpur, go to Salt Lake and do the registration procedure ?

Such procedure is laid down in law and rarely, in exceptional situations, registrars do that thing.  You contact the registrar and if he is willing to travel to Salt Lake your problem will be over.

2. Can a Registrar from Salt Lake under any special circumstances do the registration procedure ?

No.  He does not have jurisdiction as such.  If either you or your fiancee shows a residence proof of Salt Lake, he will be competent to register your marriage.  Contact local advocate and he will show you the way.

3. If we do the registration after the ceremony (on the day of reception) at Barasat, do we have to give notice as required for registration before marriage ?

Special Marriage Act registration demands minimum 30 days prior notice.

4. I want to keep my own surname instead of taking my fiance's surname. If the marriage regsitration is done after the social ceremony, will my surname be changed by default ?

No.  You can keep your surname.

5. As I will be joining my fiance in LA, USA after marriage, should I go through any special type of marriage registration (I heard something about apostile or getting stamped by MEA) ? How long does this procedure generally takes ?

Most of the countries prefer marriage registration under Special Marriage Act. 

A marriage can be registered at the place, when the marriage has taken place. You get your marriage registered under Special Marriage Act after having undergone the ceremony. Download the Special Marriage Act from the "Share file Section" of this website. I have probably uploaded the same for guidance of various couples. Notice is mandatory and it cannot be dispensed with. Similarly, a marriage will be registered by the Registrar only after a lapse of 30 days period of notice. The name has to be mentioned in the marriage registration. You may not change your surname in any other documents. If need arises, you may show the marriage registration certificate. However, I doubt, the passport authority may not entertain such request of keeping your parental surname. Try it.