A lappy with a 17" screen size and tat too in 45K budget is NOT possible.. looks like u are probably looking for a gaming lappy or for movies (considering ur requirement of a bigger screen size)
in the range of 45-50K, u will get 15.6" (in SONY VAIO E Series at 50K, perfect for gaming, entertainment, movies and also work related apps) or 16" lappy from DELL..
if u can tell me ur requirement, i can help u in a better way..
Cheers n e-peace....