What are the easiest irons to hit?

The most forgiving irons are those which have very 'chunky' heads, you should look for something along the lines of Callway and even Ping are very good. The idea of the forgiving clubs is that they have a low c.o.g and are easily able to get the ball up in the air. Clubs like hybrids are very easy to hit, and you can even get a full set of irons like this, they are called the Cleveland Hi-Bore.