NRI, as of now all funds are under NRE A/Cs so not paying any tax.
Ok....
so now i would suggest that you take this as a loan from him.... There are two main reasons why i say so..
1.) The interest that you pay to him each year would be tax exempt in his hand and accordingly you would be getting the deduction benefit for the same thus lowering your tax outgo...
2.) In case of taking as a loan it can anyways be converted into a gift if its felt so in the future but for gift that is not possible...so even after taking the amount as a loan you still have the other option open....
As for the amount to be trfd to wife what magnet has said is correct...there is no point in doing so since all the income would get clubbed in your hand...
Coming to Mr. Jhunjhunwala... Here what must have been the scenario is that she (wife) would be already having some capital to invest which she would have invested....Her invest able corpus would have been there and it was simply put to work...In your case you are gifting her the corpus itself which is not allowed....
So first generate some fictitious income in your wife's name for sources such as tuition income etc, then deposit cash in bank...and hence start the trading from there...Then it would not be a problem is you work as an employee under her.
JUST A SMALL POINTER - WHEN YOU TAKE THE AMOUNT FROM YOUR FATHER AS A LOAN OR REPAY HIM THE INTEREST OR PART LOAN BACK DO IT ONLY THROUGH AN ACCOUNT PAYEE CHEQUE....NO CASH !!!