Dude laptops & cell phones are two businesses in which the manufacturers margins are highest. The point that I am trying to make is even though your budget is 50k, look around before putting in your hard earned money.
I would recommend an
Acer Aspire 4520, it would cost you Rs. 29,990 for 1GB, add another Rs. 1250 if you want a transcend 2 GB DDR2 RAM. This is one hell of a laptop! You can compare any Rs. 50k-Rs. 70K laptop with this machine & it will win hands down.
So instead of making Micheal Dell rich, use Rs. 20,000 that you saved on a holiday to Goa.