How to clean my laptop of malware/viruses?

[roundgoose567]

I use Windows 7.

I downloaded something that would help me in making good quality gifs and I thought it was safe as on the website it had a lot of reviews which were mostly all good. It also had quotes from a lot of technology websites. However it also downloaded a lot of viruses.

I used malwarebytes to put them all in quarantine (there was two trojans and a lot of pup. Spyware and adware.) I also deleted Firefox and Google chrome assuming that more viruses might be able to come through (I know this is dumb.) However I cannot download them from browser choice or internet explorer as I believe this malware has blocked me from using it. It tells me that it cannot display the pages.

So, assuming that Malwarebytes has missed something I am doing so full scan on Microsoft's security essentials. However if nothing shows up how am I able to use the internet again? I am able to use Skype.

If you know of a solution of it please tell me if it is an easy or difficult procedure. T
I can't use the internet at all, so I am unable to download the software you have suggested. If I need expert help with trojans then I will just tell my mum that instead of risking anything. Thank you for all of your advice, I will ask the computer guy if it is possible to use avast instead. If you still want to answer, please tell me Firefox add-ons that are important to keep you safe.