iChat, repeatedly asks for password and how does an aim user add me?

[MythicFrost]

Hi I have two questions:

1. 
   Every time I open iChat for the first time after turning my computer on it says I've entered an incorrect password when it tries to automatically log into my account (I think it only happens the first time I've turned the computer on),
   I retype my password (the same one that's under iChat>Preferences>Accounts tab and it accepts it and it's fine even if I quit it and open it again.
   I've already removed and added my account again in iChat, it's becoming a little annoying.
2. 
   I was also wondering, if a PC user on aim wanted to add me would they add my myname@mac.com account I use to log in to iChat, I assume that's what they'd do, but I just wanted to check.

Hope someone can help, thanks.