Click on the hot link in my first post and it will launch you to the Autoruns download site. Autoruns is currently owned from M/Soft, they purchased it from Mark Russonvich. It is a great, free utility that will list all the items that are loading whenever you boot your computer. You may be surprised at what is loading without your knowledge. If you use the suggested "Hide Signed Microsoft Entries" option (those would be your Windows OS system files) it makes it much simpler to see the 3rd party loaders. By clearing the checkbox in front of an item, that item is not deleted, just prevented from loading on boot. Needless to say, be careful not to disable any Microsoft or Windows files unless you know exactly what it is you are preventing from loading.
If you are not running any exotic programs, Linux is a really excellent option! There is a Linux forum on this website that can help you get started, and Linux has come light-years from the geeky, hard-to-use genre it used to be. It now boasts sophisticated, beautiful GUIs, is fast, stable and FREE! Excellent choices would be Mint or Puppy Linux. If you want to try it out but not commit, there are virtual distros that load into memory and work great, such as Knoppix and others. When you are finished, just shut down and the OS ends.
I understand that some folks use the virtual distros and just let it run 24/7, that is how great these things are now. If you get a virus, so what? Just power-off and everything disappears. Reboot and the virus is gone and you are back in business. Peruse the Linux forum, there are lots of enthused, happy users there that will be glad to help you.