ICloud :: Can Keep Email Running Without It

I am using Mac OS 10.4.11 and I do not plan to upgrade my OS software at this time. I am not using any wireless devices such as iPhone, iPad, or iPod.  The only "wireless device" I use is my PowerMac G4 using Airport and whatever wireless signal from a modem is handy for internet connection.  I am using Apple's Mail application and wish to continue using it just as it is with my existing email addresses.  I currently have a MobileMe account which I'm not worried about losing when it's phased out as long as my Mail application and email continues to function. My question is do, I have to sign up with, or make the move to, iCloud in order for my Mail application and my email to continue working in the near future?  I do not mind losing MobileMe and I do not mind not having iCloud if my email will work without it. I do not wish to purchase iCloud service and I hope I do not have to pay to keep my email working. I do have iDisk at the moment but I prefer to let it go rather than to continue to pay for a remote upload/download storage service, although I wouldn't mind keeping it if I don't have to pay for it. 

Info:
PowerBook, Mac OS X (10.4.11)