Start with cleaning off cookies and history from your browser.
Also if your still using internet explorer, consider switching to chrome or firefox
Use the disk clean up tool, and maybe a defragment tool if it needs it.
Consider what kind of anti virus you use. Some anti viruses use more resourses than it should, on older computers that slows it down tremendously. McAfee is the worst culprit in that catagory. Norton or Avast would be what i recommend. Avast is completely free for a year.
Clean up by organizing the random files just sitting around into folders.
Go through your programs in the Add/Remove list and look for programs that you don't use. Anything from Microsoft don't uninstall, usually those are important, but you should be able to tell which ones you installed.
Use CCleaner or go into MSConfig and stop programs from autobooting that you don't need to autoboot (that you know what it is). Example STEAM especially if you don't game on your laptop all that often you can stop it from autobooting, along with most office productivity suits have a habbit of autobooting things, etc. (oh looks like fkr covered that with autoruns)
Oh and if you have a HP printer and use their normal drivers get rid of it, their a huge resource hog. Just uninstal all of it and see if your computer recognizes the printer. If not go to their website and download their stripped down driver which is nothing but the driver and I know in the past they didn't include the basic driver on the disc provided you have to download it off their website.
And to just add to the list of things to use for antivirus MSE (microsoft security essentials) is quite good as well, I pair it up with windows firewall with great success. Very light on resources and it works.
Invalid registry entries created due to regular installation and un - installation of programs and applications. Chily Registry Cleaner Software is reliable tool for cleaning all invalid registry which will completely scans the system registry and making the Windows registry error free.
try this one and see if it finds anything that yours does not. I am always looking for better free software.
Wise Registry Cleaner(some people do not like these): http://www.softpedia.com/get/Tweak [...] aner.shtml