Windows 10 Virtual Machine Malfunctioning

I am running a Windows 10 Virtual Machine. The Host is Linux Mint 19.1.

I admit, my computer is a little light spec-wise. But, I don't think things should be running this poorly.
It's an i3, 4th generation or thereabouts, 8 Gigs of DDR3 ram, desktop.

I am on the latest available version of VirtualBox

I have tried allocating 1 core and 2 cores to Windows 10, 3 GB of RAM and 4 GB of RAM.
The highest that VirtualBox will let me go on video ram allocated to the machine is 256 mb. I have always kept it set at that.

Here is where I have noticed unbearably poor performance:
1) press start button, then start typing in search words. It's very slow, I usually just hit the escape key instead of waiting for 30 seconds to see if it does anything.
2) press the start button, choose settings, then click on system. It then freezes. I have waited 60 seconds and nothing happens. When I minimize that window and then expand it again, I think it will then display the "system" screen. But, that screen's frozen. Certain clicking will turn the whole virtual machine black. Once when I clicked on "power & sleep," it brought up the "multitasking" settings.
Installed programs seems to work reasonably ok (a bit slow but reasonable)

I don't think the performance used to be this bad. My guess is that a Windows update somewhere along the way made things worse.

The other virtual machines that I use are not this bad. The Linux ones seem quite fine. Windows 8.1 seems ok but then again I haven't duplicated the above actions there.