Good Chess Programs

Hi everyone!  I've only been playing chess for a little over a year, but I have progressed quickly in that time.  No one in my family is really good and helpful towards becoming a stronger player.  Something that helped a lot was a classic boardgames game with chess as one of them that I could play on my gameboy.  Now, it is too easy and does not challange me at all.  I was wondering what kind of programs you all might suggest and why they are good to use.  Please write and thanks!