@LukeAlmighty the best method would be to upgrade them to an SSD.
when i got ahold of my grandparents' computer they had like 3 different antiviruses installed (two of which i've never heard of) because they got it from some prebuilt place too so that's a good thing to look for.
@beardalaxy
I know...
But also, do not forget, that she has an up to date legal Windows, and that means also up to date "telemetry" and updates, that need to be extracted on background using new compression algorithms etc.
New win 7 and old win 7 are not the same.