In a large bowl, cream the butter, peanut butter and sugars until light and fluffy. Add eggs, one at a time, beating well after each addition. Beat in vanilla. Combine the flour, oats, baking soda and salt; add to creamed mixture and mix well. Pour into a greased 15x10x1-in. baking pan.
Bake at 325° for 18-20 minutes or until a toothpick inserted in the center comes out clean. Immediately sprinkle with chocolate chips. Allow chips to soften for a few minutes, then spread over bars.
For glaze, in a small bowl, beat peanut butter and confectioners' sugar until smooth. Add enough milk to achieve spreading consistency. Carefully spread over warm bars; sprinkle with peanuts. Cool before cutting into bars.