For exhibits, should i file certified copies or originals in court?

Now if you apprehend that your aunt may not misuse the documents better is to lodge an FIR in the police station and keep the copy of FIR, and police will record the statement of your aunt for tell them you doubt the documents are with your aunt.

I think you are confused with certified copies and attested copies. 

Certified copies are no less than originals and if you have really certified copies and you want to submit them then there is no need to file originals.

If you mean attested copies then for sure you can submit attested copies upon filing and once there is stage evidence you can file list of documents with originals.

Certified copies are treated as secondary evidence for which you need to seek permission from court whereas original copy is primary evidence so better file original copies in court a d avoid controversy. 

Thank you for valuable advise sir

At the time of filing the case you can file the cetified copies ad you can replace the certified copies with original documents at the time beginning of trial.