this summer, either from the heat or from my home shifting, 2 of my interior doors are rubbing against the door frames (sticky). to correct this, do i sand down the top of the door or is there a better way? thank you.

Our wood frame glass patio door is rotting out at the bottom. Hubby and I plan to replace it and want info as to our best option. We live in Iowa (cold and windy winters!!) and the door has a north exposure to the winter winds. We're looking at every option from the $400 budget doors to the $2400 high-end with triple glass and inside shades. We wouldn't mind paying the price (and the installation) if we know the end product will do a good job of sealing against the cold. We note that some sliders are on the outside with screen on the inside. Some have the screen on the outside and the slider on the inside. Some have that fuzzy felt type gaskets. Some have rubber. Different sales people tell us different things. Can you give us recommendation as to what is "a must" and and whether the high-end models actually are warmer? Thanks.