Force feedback - is the sensation where you can feel the rumble strips/potholes on the road through vibrations on the wheel. Basically a form of haptic feedback.
Not so sure about the other two, but I think linear resistance means that the wheel will provide increased resistance on turning it more, resembling an actual steering wheel, and will probably centre itself.
Thrustmaster is a good name when it comes to racing wheels. Other alternative is Logitech. Haven't come across the brand names you have mentioned, other than Frontech which I'm sure will be not worth spending much on.