Question: For example in Peggle or Apple Jack, the user can move around a curve showing where the ball (or the washing machine / panda or whatever) is about to go before the user has requested that the projectile is launched. I know i need to use an equation to plot the points but I'm no mathematician (anymore :(). Can anybody be so kind as to provide me with the correct equation and tell me what I should substitute in to get my X any Y values given a certain time and initial velocity.

Answer: 
Simulation would probably be the **easiest** route to go down: create a dummy object with the specified properties and create a loop to apply the forces and say output the positions to an array and then display it, say: draw a line between the positions or draw a "ghost" of the projectile at each position.

A positive thing about simulation is you can control the balance of speed and accuracy by changing how often you record the positions.
If this is a projectile following a simple ballistic trajectory, you can use the closed-form expressions provided here:

<http://en.wikipedia.org/wiki/Trajectory_of_a_projectile>

If not, it might be a lot simpler to simulate the effect of all the forces on the body for each (small) time-step, updating its position and velocity accordingly. This technique is more robust; you can add a lot more complexity to the problem without changing the basic methodology.