Why is Chrome still on my pc?

Hello! So, last week I had a mini saga involving finally getting my FF updated. I have a superold pc with XP. My browsing is very slow now though, slower than before the update and I'm trying to figure out why. A year or so ago, I tried Chrome but the pages kept freezing and I thought I had deleted it. But now for some reason there are scripts still running and getting stuck. Why is it still on my system, and how to I get rid of it entirely? In general, every little adware and whatnot seems to slow this puppy down. I watch the bottom of the screen and I have no idea why FB is following me around, and heaven knows who else. (Of course, it is time for a new machine. But meanwhile...) All suggestions appreciated!