When attempting a run, what kind of save file is used? is it standard or just whatever save file you have. should some categories start from a new save file?

This game is a current favourite of mine right now and I'm thinking of trying out some of these categories. What is up with the "Display Mode" option?

Edit: clarify, is there a difference in gameplay or tangible speed benefits in VR Mode?

My friend Yaram has created an autosplitter for versions 1.11.2 and 1.12.1, which is now available through LiveSplit or via her Github.