Trini, first off, the rear of the car has shocks, not struts. There is a slight different between how the two do their jobs for the car. In short, shocks only dampen movements between the body and suspension where the struts provide some portion of the weight bearing ability of the suspension and normally provide some turning function too.

As for replacing the rear shocks. All that takes is removing the lower mount, undoing the upper mount and the shock will be able to be removed from the car.

As for the front struts. This is a fairly involved process. There is a lot of stuff that you are going to be removing. But, I will try to summarize it here:
1) remove front wheel
2) disconnect sway bar from front suspension (make sure both front wheels are off of the ground and the jack stands are located on the front half frame, not on the suspension itself)
3) remove the brake caliper and rotor from front spindle
4) loose up lower ball joint, break joint loose.
5) loosen bolt holding the bottom of the strut to the spindle
6) Remove strut from spindle (may require removing the lower control arm at this point as the control arm may prevent enough downward movement to get the two pieces apart).
7) Undo the 3 nuts holding the strut to the body of the car
8) remove the strut from the car, apply spring compressor to provide compression to the spring and then remove the nut holding the top cap to the strut. From here, slowly remove the clamping force to the spring to remove any spring tension
9) disassemble the strut assembly and install new strut
10) reverse steps to install.

 

Are you saying it doesn't matter what your actual speed is, it's tied directly to the RPM? If you shift into second or third does it go away until you get back up to 2500?

My first though was a bad (or loose) hub.