Want to delete gmail email address used in settings. How do I do this!?

[NeedToKnow]

I deleted my gmail email address because I was getting 150 spams or more A DAY, seriously. I just went into my settings to delete that email address from my iPad2 and noticed it is the email address for my iPad. I tried changing the address to a different gmail address but it still shows the deleted one. What will happen if I just delete that account? The red bar below the gmail email address info in the account settings. Will I be allowed to set up a new one or will I no longer be able to use the Google calendar and any apps that are connected to it? Unfortunately some apps I have use that stupid gmail calendar that I hate. I have NOT updated to the new iOS for myniPad 2. I refuse to lose my YouTube and Google Maps. I also am not sure what other apps will no longer be able to be used if I do.

Will this same answer apply to my new iPhone 5? I know this is not an iPhone forum, but I have both. Please don't start discussing iPhone here escept to answer that one question as it pertains to my iPad 2 question.

 

[NeedToKnow]

Update and new question connected with the first question. I turned myniPad off and then on. The other gmail address now appears in the settings and I have deleted the other one as that gmail address was deoeted from gmail and I did the smae on my iPhone. Now the other question that is connected to this same issue. If this gmail email address gets spammed like the old kne, do I have to use a gmail email address to be cinnected to the gmail and other google items needed to be able to access cerain apps, ie calendar, etc.? Can I use my Pop3 address through roadrunner that does not get spammed or does it have to be a google email address?

Thanks.