I guess you missed that Bush kept the Iraq and Afghanistan war cost (and many other things) off the books, which was dishonest, and Obama put them back on.  He probably knew many people would not be paying attention and forget he did that, but he did it anyway, because it was the right thing to do.
And yes, the debt DID explode under W, especially as percent of GDP.  I challenge you to provide evidence to the contrary from a reputable source.
I cede that the correlation between Presidential party and deficit is correlation and not necessarily causation (although you have to admit it's a heck of a correlation).
http://www.nytimes.com/2009/02/20/us/politics/20budget.html