Bear in mind this is a guide only. I would suggest using CCleaner\Tools\Startup to "disable" startup items you know you don't need, and any you're not sure of, do a google search for them as there's plenty of info out there. And then disable one at a time, and if all runs fine, disable others.
If you have any problem afterwards, simply enable an item again with CCleaner.
Don't delete any items as you won't be able to enable them again.
And if you haven't already, have a read of the CCleaner guide. There's a link to it in my signature.
Malwarebyte is fantastic : it found 5 malwares on my machine ! Thank you very much, merci ++ comme on dit chez nous .
Winpatrol is very interesting but big, very big, too big for me. I am going to explore it but I knew something looking like this called "SIW". Piriform products are more simple and easy to use. Thank you Yokenny I love Canada "souviens toi"
Martial, I don't want to be the bearer of "bad tidings" at this time of the year, but if Malwarebytes found 5 malware items on your pc, there could well be more that haven't been picked up.
I would strongly recommend following the advice at this link, to ensure your PC is actually malware free. It won't hurt to check it out just to be sure.