What if the earth was not titled?

The important thing to note is that once an object exceeds a certain quantity of mass, that mass pulls itself into an oblate spheroid by the very nature of gravity. Therefore, the only bodies in the solar system of which we are aware that are non-spherical have minimal mass.

If, however, we were to suspend the laws of physics as concerns the above-mentioned fact and hold that an object as massive as the Earth could be as irregularly formed as say Phobos, there would be a massive number of changes in life on Earth. Firstly, because different locations would have extremely different distances to the center of Earth's mass, gravity could be as much as two times stronger at the thinner region than the thicker one. This might cause there to be habitable and uninhabitable zones of Earth since there would be regions where the gravity applied might be too taxing or may liberate too much atmosphere (think about altitude-sickness). The tides would certainly be affected and there would be an increase in storms because of the vast atmospheric differences between regions. There are a number of other effects, but those are the most important.