Irrecvdemo program in or remote library gives fatal error #include
You are using a very old library on a modern IDE.  The file that was called WProgram.h in IDE version 0023 and below is now called Arduino.h.  You will need to change any references to WProgram.h to Arduino.h instead.

Well written libraries do this with a #ifdef block:

#if (ARDUINO &gt;= 100)
# include &lt;Arduino.h&gt;
#else
# include &lt;WProgram.h&gt;
#endif