It is going to depend on what is in the document. If it were simply text, I doubt this would happen. It may be related to your display adapter, especially if you got suckered into installing Win 10.



Consider using Collapsible Headings and the Navigation Pane for moving around/scrolling. Why use Microsoft Word’s built-in heading styles? by Shauna Kelly

Use Styles for most of your formatting. This makes for a much less complex document structure. Understanding Styles in Microsoft Word

Word 2007 has no problem loading, editing or scrolling this document up and down. This is on Windows 10 x64 with 8GB of RAM and a two-core processor. But my version of Word is installed on a SSD, and so are its temp folders. This might make a difference.