Computer slow, pixelated/scrambled mouse

Hi - My computer momentarily freezes, my mouse becomes scrambled, the shape was distorted and the color was cyan and yellowish and the cursor itself isn't at where im clicking (im actually clicking 1cm to the left of where my cursor is showing).

The problem persists and every 10 seconds or so my computer would freeze for around 3 seconds, I checked task manager but there are no processes there.

I restarted my computer and it took quite a long time to shutdown, being all laggy, the problem disappears for a bit then reappears. I'm guessing it's a virus or something but thought someone here might know.

Any ideas? Thx.

Thanks for the suggestions! I ran a Malwarebytes and checked for disk errors. No disk error but it did turn up some threat, a file downloaded ages ago that is now 'quarantined'. Not sure if that was the problem but I haven't seen the problem again in the last few days. I've also been running Advanced System Care's Game Optimizer for several months. Never had a problem when I've run it before but perhaps some changes to the optimization settings that I made recently can cause my problems? I also updated my video card driver before this happened. Anyway, will be in touch if it happens again. Thx!