Totally off-topic but... To turn off ads and offers, open Options > Preferences > Advanced. Here you'll find a large list of flags for the app and a filter box. Search for and disable the following flags: offers.left_rail_offer_enabled gui.show_plus_upsell offers.sponsored_torrent_offer_enabled bt.enable_pulse gui.show_notorrents_node offers.content_offer_autoexec
There are two taskmgr.exe files. The one in the system folder is the real one. The ones in anywhere else is a trojan most likely. Any malware can be named anything - so you should check where the files of the running processes are located on your disk. If a "non-Microsoft" .exe file is located in the C:\Windows or C:\Windows\System32 folder, then there is a high risk for a virus, spyware, trojan or worm infection!
It's worth checking out when the bad taskmanager file was created (right-click, properties) and see if date corresponds to any particular program installs in "Programs and Features," "Installed On" dates. Get a sha1 hash of it and google it, dunno.