Too bad I didn't study physics

My knowledge of physics consists of a single high school course.  Aside from that, I have no formal schooling on the subject.  So, what comes next may be taken with an extra large grain of salt.

Since I first saw the Dense Plasma Focus concept, I've been intrigued by it as a potential propulsion system.  This interest just increased when I saw this Wikipedia entry on the subject of fusion.  The idea that grabbed me was the caption on the right side of the page which includes this equation:

kinetic E = Δmc², where Δm is the change in rest mass of particle

This grabbed me because the fusion reaction produces "kinetic" energy.  This is the kind of energy that you want for a propulsion device.  Does this mean anything significant?  Well, I wish I knew, but I don't.  I know that the c squared part of this equation is a very, very large number.  And m, meaning mass is a very small number for a single atom of helium four, pictured with the mentioned caption.  "Mev" means million electron volts, if I am not mistaken.  It must be a lot of energy, because the reaction is far more energetic than fission, which yields plenty of energy itself.

What is the practical effect of the change in delta m?  What velocity does this mean in terms of kinetic energy?  It must be a large number, I would think.  It would seem that if this reaction can be produced with enough mass, then considerable kinetic energy can be formed.  There would be no need to heat up a reaction mass as the kinetic energy thus supplied could be significant enough in its own right to propel a spacecraft.  That is what interests me.