Safari preferences homepage fields grayed out

Hi,

After running Malwarebytes and successfully quarantining some suspicious files, my MacBook Pro is running well except for one new issue: Safari will only open to a blank new page now. The fields for "New Windows Open With", "New Tabs Open With", "Homepage" and "Set to Current Page" are all grayed out.

Any ideas? I've checked for updates and am up to date. Can't figure out what else to do--

thanks for any help!