mine is doing this, doesnt really take off until 6000 RPM, no idea what is wrong but there are a few things i need to change, and some sensors that i need to fit.
as for the clutch, do as joel suggests, but it will make a difference, just adjust it until it feels right.
The clutch pedal has a threaded hole on it that pushes a threaded pushrod that goes to the master cylinder. This pushrod is locked in place with a nut that is tightened against the threaded hole.
to adjust, loosed the nut and spin the pushrod to achieve the level of adjustment you want. the first time you do this it is necassary to lie on your back under the steering wheel, but after that you know where all the bits are and can do it sitting in the drivers seat.