I am the personal representative for my moms estate which is in probate. What options do I have if I don't want to sell the house, but my brother does

As personal representative it may be your duty to sell the home if the funds are needed to pay the estate's bills or to make distributions under the Will or, if there is no Will, under the state's laws of inheritance.  Your alternative in the second instance would be to buy your brother out (and to buy out anyone else involved).  If this is not possible, the house must be sold and the net proceeds split.