Hello there!!
It seems you don't have an SSD, the most inexpensive way of getting your system responsive is by installing a SSD which id recommend.
The first responder is the best answer/solution without a doubt. If you're unaware of the difference in performance, you're in for a stunning surprise! Not only is it your biggest and best upgrade to system performance, it'd almost certainly be the cheapest as well - a 500 GB SSD can be purchased online for as little as $40, possibly slightly less. If you're as impatient as I've been under similar circumstances, you can get one from Wal-Mart for about $50 (500 GB).
However, some of the other hardware components in your system are beyond the 'outdated' mark, sadly & unfortunately... so if/when you upgrade the hard drive, I'd almost consider it the first of 3 or 4 that will need to be made within the next 5-7 years. Ordering piece by piece over a span of 6-8 months actually seems much easier on my finances, personally, and cheaper than purchasing a pre-built system, without a doubt.
Alternatively, should your financial situation eliminate this upgrade option altogether, I would suggest running through a full "tweaking" list - i.e. disable non-essential services, disable all startup programs, defragment, turn off all 'visual' options (the bells and whistles of Windows), and perhaps even play with the Performance Monitor console included with the Windows 10 operating system.
If you're not familiar with the program, it allows you to monitor any and every system activity, function, and/or behavior in real-time, displaying detailed statistics and illustrating them in line graph form. The only real hard part (for me, anyway) is finding the specific system resources I want to begin monitoring within the monstrous list of choices.
Easy answer: Upgrade the HDD to an SSD. Major performance increase will be guaranteed.