No. Data that isn’t accessed doesn’t really get in the way. It’s possible to re-organise the information on your disk to keep all the frequently-accessed stuff together though (it saves the wee disk head zapping back and forth so much). Ideally, you’d want to partition your disk into a “drive” for the operating system and programs and another “drive” for all of your data (books music, pictures etc). Thing is, this can be difficult to do without a clean install of Windows (something you might find useful anyway).
Another option is to pre-allocate a swap file. That’s a highly-used area and keeping it contiguous will improve performance.
But before you do anything, get an external Hard Drive and back up everything you have!!!