spy and malware warnings

spy and malware warnings from firefox and Internet explorer. also warnings not to make purchases on line.
should i be concerned, i called the # they gave, and they wanted to charge me, and i replied, i am with webroot , and i have protection, so i will let them check it out, because i have been with ya'll for 3-5 yrs and still going, so i trust you and no one else, well besides the geek squad, they r good people as well. thanks!
                                                                                                                 chow