Which is the best website to open an online trading (demat) account, for a beginner/layman?

U can with ICICI,SMC,SHAREKHAN etc. But ICICI are too much costly and highly expensive for small trader ICICI as it claims doesnâ€™t always charge 0.75% on Equity delivery (mostly in my case).
I am not a big trader I keep investing small amounts and also not a daily trader but an occasional trader.

These are the various percentages at which my brokerage was charged at:
2.5, 0.78, 2.36, 0.91, 1.61, 1.9, 1.74, 0.75, 1.14, 0.94, 1.41, 1.37
If your trade is beyond 3300/- then the claimed 0.75% aplies to you else the transaction charges are always 25/- or 2.5% flat(for less than 1000)
At Present I work with sharekhan they take only 0.30% Brokerage. & service is very good. My experience with Sharekhan is for almost one year now. Opening an account with Sharekhan was a pretty smooth affair for me. It is really amazing to see Sharekhan having links with more than half a dozen
banks for money transfer. Consider this with the fact that Reliance Money does not have arrangement with ICICI bank whereas Sharekhan has. The way they charge is quite transparent and as per their promised tariffs only. I never found any deviation. Transacting online with them is pretty smooth experience. However I am disappointed they do not have any special offering to small and medium intraday traders. They charge 0.1% plus taxes for each leg of intraday trade. Thi is something I could not afford with intraday trading. So I chose to do intraday trade with Reliance Money and delivery trade with Sharekhan. I would like to shift to Reliance money only after observing their service for a while. With Sharekhan I feel pretty safe of my holdings in their DP account. If Reliance money is also having good service, then I would move my holding there to get maximum benefit. The reason why I am referring to Reliance Money is that I am very disappointed I have to leave the excellent service of Sharekhan for the sake of saving brokerage only. May be Sharekhan would come out with a nice brokerage plans for intraday traders, then I would be the first one to come back to their services. So the lesson one should learn so far is Sharekhan is not good for daytraders. But I believe it is the best option available in the market for long term investors who do ocassional transactions. Long term investors could benefit from the recommendations Sharekhan provide. Most of them reach target. TFCI is a fine example in recent times. Their customer service is excellent. If there is any deviation in their service, they would inform you at least one day in advance. I had one experience of them informing me about the 2 day delay in crediting the shares of a company into my DP account. This kind of service would ensure that we do not have to worry about any wrong doings with our DP account. I suggest Sharekhan account to all those ocassional traders with or without any knowledge about stock markets.