It depends on your use case. Both Parquet and ORC have their own advantages and disadvantages. If you go with Spark then parquet is better because Spark has a vectorized parquet reader and no vectorized ORC reader. But it also depends on "How nested is your Data and how many columns are there". They uses a hierarchal tree-like structure to store data. More the nesting deeper the tree.
But ORC is designed for a flattened file store. So if your Data is flattened with fewer columns, you can go with ORC, otherwise, parquet would be fine for you. Compression on flattened Data works amazingly in ORC.
Hope this will give you some idea.