Samsung Galaxy 551 vs LG Optimus One P500!!?

I'm from India and want to buy an Android phone. Samsung Galaxy 551 is better or LG Optimus One P500?? My main requirements would be Wi-fi, messaging and most important all games and apps should work! Galaxy has lesser screen resolution, so will it be a hindrance in the working of games and apps or no? Plus Optimus has 512 MB RAM as compared to Galaxy's 256 MB!!?? Please its urgent!!!!!