I have used samsung many cell phones and I used this cell phone also and I faced same as all Samsung Galaxy Grand.
It also has the same problem of getting hanged every time. It has 1.5 GB of ram then also it gets hanged every time I dont understand why it happens samsung should see to it that its no smartphone gets hanged because money is very precious so I dont think that we have to buy the cell phone which has the problem of getting hanged.