You also don't specify which of the HD4xxx GPU's you have. The "4600" is much better than lower numbers.
You can Google for "Minecraft" and your exact GPU (find the CPU name), or use CPU-Z, or GPU-Z.
As per the above comment, you'll need to tweak the settings including the Resolution (recommend 1600x900 or possibly LOWER resolution).
Use FRAPS so you can view your frame rate (as said, want at least 30FPS).