The way you describe it I'd urgently recommend a full harddrive and registry cleanup. Also, check your autostart folder and decide if you really need all these programmes running in the background.
Another important point is: delete cookies, temporary files and empty the waste basket.
Don't keep files on the desktop. Only keep links to the files there. It'll speed up your laptop considerably as everything on the desktop has to be loaded when you power the laptop up. Links are tiny, compared to files, hence the greater speed.
A slender OS starts faster and is more stable than a bloated one.
The registry cleanup is tricky for a layperson (it's open heart surgery on your computer) and I recommend you play it safe and use a special software for that one and back up your registry before you delete anything. Still, tidying it up really pays off. It might also solve your update problem.
(btw, I use 4 machines: 1 WinME, 1 WinVista, 1 Win10 and 1 linux

all 4 run smoothly)