I always think of System Restore as the last thing to do if all else fails, because it can sometimes require a lot of Up-dates to be installed to put everything back in order and sometimes confuses the Operating System.
Personally, I would click open the Computer Panel and then click Programmes and Features; from the list of installed programmes, find Chromium and uninstall it.
By all means then install AVG and Malwarebytes and do scans with both of them; which should clear-up your problems. Perhaps then you should install what I consider is the best of Browsers.....Firefox.
Hans.