Call of duty 2 is worse than the early versions in the series, They have made it very easy by the regenerating health funda . if u r low on health just take cover for 5 seconds and guess what u r fit as new. This builds no tension.you can just run into the enemy and kill everyone as even if u get hurt, just take cover for 5 secs and u r back, or if u die u will start from somewhere very near as this game has lots of chkpoints. Graphically the game looks cool but the whole experience is not satisfying.
GRAW is the game for u if u love the idea of no quick saves , only chkpoint saves that too come after long intervals, 2 shots bullet will kill you(and the enemy as well), no funda of health. once u r low on health,no chance of getting a health pack. The game has cool element of strategy, you control three squad members. The physics is awesome and the story is good. You can enjoy this game only if u have patience. Graphically the game is cool(newest patch introduces screen smoothing option to it) although little bit more system requirements than cod2.
The two games u r asking abt are totally different , COD2 vs GRAW is Mayhem vs tactics. choose the game according to the type of gamer u are. Both are good games your money will not be wasted whatever u choose.
My suggestion : GRAW.