I want to partician my Acer x1935 desktop. I want one partician for the images from the Dell machine with XP and another partician for other images and text documents.I have Windows 7 and 10 on a dual boot, even though it says "Windows8Acer on the screenshot: https://photos.google.com/photo/AF1QipNCVrvBTEurEiT2gGjrfjBa1SWPN2hzZvTKY-RD
Your link doesn't work for me. But only you can determine what size to make the partitions(this is the correct spelling) because you can determine how much disk space the existing files need and how much additional space you might need for these files in the future. I recommend you don't make a partition for every image or every machine, just make a Data or Backup partition and create folders for different images, computers or files.
Behind every good computer... is a jumble of wires 'n stuff.