Voting and nominating

Hello

Can anyone please help me. I am building a site for a client and they have asked for a page where they can nominate and vote only if you are a registerd member.

If you are not a registered member it will take you to a registered screen, once registered it emails the user there username and password.

I would like it once they login it takes them straight to the page. at the moment it takes them to there profile page which i dont want it needs to go to the page they have logged into.

Can this be done if so how can i do this? I am at a loss and would appreciate some help.

Thankyou