Is this a fault of my computer?

 From:  Michael Gibson
1275.2 In reply to 1275.1 
Hi Rudy - your head piece is made up of several individual surfaces, it is not currently a single solid.

So what I think was happening is when you went to boolean it, you were only grabbing just the outside surface as the first object to be selected, probably the separate "inside" surface was not selected, that's why it would be hanging around afterwards.

If you make sure to select everything in that head piece, like for example by dragging a window around it, then it should work for you.

It may be a good idea to join all the pieces of that head piece together so that it is one solid piece (it needs a bottom cap as well), then that makes it easier to deal with it since it will be one object that gets selected with just one click on it.

Does that make sense?

Also at this point you may want to select some of the construction curves and either delete or hide them to get them out of the way.

This one was not probably any problem with your machine, but more RAM is a good idea to keep things from bogging down anyway.

- Michael