I used Samsung Galaxy Star which got the same specification. The phone was fine and smooth for three months from the date of purchase. There after I faced a lot of hanging issue. It gave me a hard time to attend calls, read SMS, unresponsive keyboard and launching apps. Then I found a solution which didn't completely solve the issue but situation improved than before.
We know Samsung uses its own UI - TouchWiz. This UI runs many services by default which makes your phone interactive. It consumes more RAM whenever you launch a new app. I found a trick where you need to install only the apps that are below 15 MB. So these kinds of apps won't consume much memory. Even if you improperly close the app, 15 MB apps won't cause much trouble to your phone.
I am now using Opera Mini instead of Google Chrome, using Facebook in Opera Mini instead of installing standalone app. Try to avoid installing the app and make use of web browser to do the task. Most of the app now we use can be launched using website, for example Flipkart, Amazon, Quora etc.
Use 4GB memory card max. I tried using 16 GB memory card in Galaxy Star. It takes lot of time to read/write when compared to 2GB/4GB memory card. In hardware we have memory address. This memory address decides how much external memory you can mount. In Galaxy Star maximum memory I can mount is 32 GB. If I mount 32 GB all the memory address will be allocated. It creates heavy load to the phone.
Install Greenify and Xposed framework. This app need root permission. If you are familiar with rooting stuff it is a piece of cake. The Greenify app hibernates the apps that are not used for a particular amount of time. It will be pushed out of the RAM. To run Greenify app you need Xposed framework. You can find more details about these apps in XDA forum.