Assuming that you still have no response and still cannot get a refresh to work or the battery removal doesn't solve the trick you may need to do a factory reset. Try this:
1.Turn the power off. If your Samsung Galaxy S 4G is frozen, pull the battery out and reinsert it
2.Hold the Volume Down button
3.Press and release the Power button
4.You are now presented with a menu that allows for Fastbook, Recovery, Clear Storage, and Simlock
5.Select Clear Storage by pressing the Volume Down button
6.Press and release the Power button
7.Now simply confirm your decision: Volume Up for YES and Volume Down for NO
Know that everything will be wiped clean however. If you need any further help please ask.