Whats the difference between southern blotting analysis and Electrophoresis?

Yes.  Electrophoresis is a required to d a southern blot. Electrophoresis separates the DNA or protein based on size.  Smaller pieces move faster through the gel and are found furthest away from the well.  Larger pieces travel slower and are found closer to the well.  In electrophoresis you can get information on the entire sample.

With a southern blot, though, you can get information about a specific fragment of DNA.  You transfer the gel to a membrane. And this membrane is hybridized with a probe that is specific to a certain DNA sequence. That probe is labeled somehow so it can be detected (as with a radioactive label).  So, with a southern blot you can find out if a specific sequence (ie ATGATGCCTAA) is occurring in your sample, and where.