Hi,
I have installed 1.2.2 ZenPhoto
I want to have User Login on the Front (Home) page, can any body help me on this.
I want to include My logo on the Home Page, don't have good idea about PHP, required your help

There is a plugin--user-logout that has an option for a login form. But for both this and your logo you will have to make modifications to the theme. This means understanding at least a little about PHP.

i am using default theme, can you please let me know where to change and what to change?

The example theme is similar to default and uses the printUserLogout() function for the login form. That should give you the necessary hints. The effervescence+ theme allows for a user defined logo. Look at that theme for your hints.