A bag forming apparatus and method that features a single drive unit for operating both a drive roller and cross-cut mechanism with the drive motor assembly being internalized within the drive roller. The bag forming apparatus and method also features a easy slide in, slide out edge sealer and vent hole former inserts that are held by, and move with, the bag width adjustable driven rollers. The edge seal inserts feature a heating element that is compressed against the film material by an internal bias in the edge sealer insert. A heating element can also be used for the vent hole inserts. The heating element can be a plug-in heating unit easily inserted and removed from the remainder of the insert.