1) Not Sure.. Maybe.
2) Yes, definitely
You got an aftermarket cooler?

At stock it'll bottleneck.
The FX4100 has always and will always be very mediocre.
Overclocked, you'll elevate it, but there will always be games which bottleneck (But that not always a problem)

Well, the FX4300 and Phenom II X4 955 trade blows depending on the situation, I'd have to say the FX4100 is slower than the Phenom II X4 955, amount will depend on the situation.