1. You are deficient in providing details,
2. You shall have to state how your ancestral property was transferred by your Uncle to his wife showing it as his property,
3. For filing a criminal complaint/case there shall have to be a crime on which any section mentioned in the IPC can be charged,
4. What crime your uncle has done in the instant case? Has he faked any document or forged anybody's signature? Without knowing tha fact as to how has he transferred the ancestral property to his wife, proper advice is difficult to be given,
5. However, if you find that he has in the process committed a crime, you can file a criminal complaint/case against him,
6. Additionally, you shall have to file a partition suit so that he will come out with his version of facts and the documents which you can counter fittingly.