1- what I need to do to convert both accounts to NRE ?any documentation required?

Existing regular accounts in India cannot be converted to NRE A/C and have to be converted to NRO A/C.

Usually foreign passport/Visa/PR card will suffice. If you can, please contact branch manager for exact documentation.

2- Are interest rates same for both accounts ?

NRO interest rates are almost same as regular savings accounts.

3- Reg $$ I think not all branch deals with such accounts--only NRI branches deal with $$$$

All branches of Nationalized and private commercial banks deal with NRE A/C. [if some branch do not deal, then it is more of an exception than a rule]. However FCNR deposits are usually handled by BIG branches. [With online access, does this matter?]

Should have rephrased my question as to the users of Money 2 India vs Online remit Sbi .
Which one you find better over other to send money to India ?