You are asking 2 unrelated questions. The D4 setting on the Sure-fit hosel is for standard lie, but adding 0.75 degrees of loft. A side effect this will slightly close the face from a standard slight open position (increase draw or decrease fade - depending on your tendency).
The weight on the bottom will primarily impact the swing weight. Swing weight is how you feel the head of the club. A 12 oz hammer has a much lower swing weight than a 2 lb sledge on the same length handle. Generally, the less general strength of the golf, the preferred swing weight is lower (i..e. C10) versus a D6 swing weight.

The Sure-fit guide can be found here - www.titleist.com/.../surefit. A local dealer should be able to help you understand the hosel settings.