Hi,
Yes - You do have IMAP and POP3 access both enabled - everyone does.
1GB is alot of emails. My work email box is around 189mb and thats going back to 2002. Of course, I don't keep EVERY email but do the ones that I need.
Google Apps are great but just remember they are free and whilst they may not get withdrawn they do have their downside like Google scanning your email for targeted ads. Although, this may not be a problem if using IMAP - depends how secure your emails are to you.
Matt