Do NOT click on them. They have fake security trojans that will try to mess your computer up. I think they popped up at Gocomics.com.
To restrict these items, click on Internet Options in Internet Explorer or Control Panel, then the Security tab, then the Restricted Sites icon, then the Sites button. Under "Add this website to the zone:" enter each site exactly as written above, then click the Add button. When done, click on Close, then OK.