Try disabling Automatic Updates

1. Go to Control Panel.
2. Click System.
3. Go to the Automatic Updates tab.
4. Un-select the "Keep my computer up to date" box.
5. Click Ok.

That's supposed to be what is making that wuauclt program run. You'll
have to do updates manually without it. That is a legitimate program by
Microsoft, but it is possible that a Trojan/virus renamed itself as
that. If you disable auto updates and it's still causing problems it's
probably a virus.

If that doesn't speed up your computer then you need to reload Windows
or get another laptop that's faster with more memory.