|Sp3cial couple of things.|
Been buying off the internet for years and its better than your local store concerning pricing. Returns are a bit more time consuming but your mom better get used to it because the local retail store will disappear in your lifetime. Retail is all about market share. Your local store can't compete with global suppliers.
You also need to understand ram usage. The OS USES ALL OF IT. Every last bit is addressed and virtualized for the OS to use. Older OS's could do this also but had issues with addressing limits due to their programming/design.
Your pagefile is not used as a last resort. It is constantly used. How much so depends on a number of factors, with how much ram in your system as primary. This is by design to optimize RAM usage and prevent the system from crashing due to running out of resources.
Just a few tidbits. Best of luck
Golly gee wilerkers everyone. Learn to Internet Search