Canon G9 or the EOS 400D

I am looking to buy a new camera. I have tried looking on the net so see 
what the difference is between compact digital and a DSLR. I am still non 
the wiser. Anyway, I have come up with either the Canon G9 or the EOS 400D

and wanted to ask here what is the best camera. I wanted to point and
shoot 
initially and then have the features there to learn about so I can grow
into 
it.

Thanks for the help