I've seen some very persistent websites like that, but I've never had to delete a user account as a result.
Simply ending task to the browser, and loosing whatever I had open in other tabs solves the problem. Sometimes, I can even get to the chrome task manager and end task to the effected tabs, but some of these malicious websites are better at bricking your system than others. I haven't run into one that does permanent damage.
Also, it might help that every time I run into those, I'm using incognito mode.
