To have buttons in rows where buttons are the same size you need to do.
<LinearLayout android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<Button android:layout_weight="1"
android:layout_height="wrap_content"
android:layout_width="0dip"/>
<Button android:layout_weight="1"
android:layout_height="wrap_content"
android:layout_width="0dip"/>
</LinearLayout>
And fill in the other xml properties for your buttons.
The magic is in the layout_weight and width properties. You don’t need the Table layout. These properties tell the layout that your views should take up equal space in the parent layout.