Well, technically, use your Gaia username for Gaia only. Same for the password. Make sure that the link is always
http://www.gaiaonline.com/ & no where else but there. It doesn't hurt checking the address bar for it.
As for the pop-ups, ignore/report them.
Any other program across the net related to Gaia? Ignore/report them.
PMs for passwords no matter how professional or/& official it seems? Report them.
I'd suggest changing your password weekly for those who are worried about their account. Make sure that it has at least 1 lower case letter, 1 upper case letter, 1 symbol & 1 number.
That's all I can say, really.
As for the "h1.ripway.com" thing, you might receive them from friends via comments or chat for a while. Er, ignore them & report the website to Gaia. Some random hacker is on your friend account. Chances of warning your friend is low since the hacker could check the mail & delete it unless you have another method of contacting them, such as Facebook or Windows Live Messenger/MSN.