You're not going to get TWebBrowser to work in FPC until it can talk to com objects. Porting the pbear.com browser would probably not be too difficult. It displays html okay, but forget javascript or flash.
There probably is no good solution here. The mozilla/delphi stuff might work ok. I've used the ie com obj extensively, and I can tell you from experience that it's not the most stable situation to work with, even with delphi.