Resetting GUI (window sizes and positions)?

Is there a command or something to reset everything back to the default size and location?

That thing there?

Yeah I think that's it, where is that at?

F11->interface, restore defaults

I'm sorry, no, that's not the fix I'm looking for.

When you open up inventory screen and you move it around, same with party etc, how do I reset those positions to their defaults?

I've always just drag and dropped them. never saw a default setting for them.

Basically, some windows such as your Inventory and Party box, have no "default" position. They have always been movable, without needing to go to the Interface panel to adjust them. You can adjust the size of those windows (Interface Size) under the Graphics tab in Options.