I'm posting this in the PHP forum as I'm programming.

I was wondering about securing cookies from hackers. So I have my login page on top of ssl, which is fine as after i logged in the cookies were secured but when I travel to a regular part of the site and I check the cookies I can see the cookies set for the login (not password, just that they've logged in). At this point is the cookie unsecured and hackers can sniff it and try to replay on that?

the users need to be able to travel between ssl and non-ssl, so what are my options to mitigating security issues?

The rule is not to use sensitive data in cookie. If you really have to, use encryption.
If you are worried about sensitive data, build the site with SSL in mind.