Would like to make your SGS at best performance and run smoothly? What you you should do is to monitor your running apps. Make sure it run as minimum as your can. Remove all the unwanted apps that run at the background.
As an example, previously I had "Smooth Calendar" app running at the background but actually it has features where you don't really need to update it in real-time. It will look for update after an hour. This could save your battery and phone performance.
Another example is, I set my TweetDeck to update manually. Means, when only I want to read, I update the content. Most of the time to save my network data usage, I download it when I'm on WiFi.
Save battery..better performance..