Not quite sure what your worried about losing by doing this, I haven't done it myself, but a quick search showed me why you may be in doubt as to what to do, I guess the main question here has to be is there anything you want to keep ?
Here is a guide, that may be clearer than you may have found so far, it may help you answer your own question, if you still have any doubts please let us know a bit more about this, and we will do what we can, but if you do please say if it is purely the email you want to ditch, or the complete account associated with that email.
The sad news with such spam, is once you start to get it that's the top of the slippery slope, you can set up filters to auto remove such emails, but you will always end up adding to it as the spam grows, the ONLY way to stop it is shut the account, as you are doing, BUT, unless you learn to keep on the lookout it's highly possible you will end up having to do this again.
The greatest ways of getting on spam lists is by not paying attention to tick boxes, and posting your Addy on open sites for all to see, if you post it on a forum, anyone can get it, and there are automated searches by spam list makers to look for published addresses, it's big business.
But not watching out for tick boxes when signing forms etc. can also get you out in the open, and although you may not be in the malicious spam lists, it's often the start of how you get there, so watch out for ANYTHING that talks about 3rd parties, passing details on and the like, because even though that company may only select what they deem to be responsible places, it doesn't mean that down the line they won't be as careful as to who gets such details.
So my rule of thumb is NEVER agree to 3rd party rules, make sure check boxes are marked appropriately, it's not as simple as a blanket rule, you have to watch out, because some places check such boxes by default, in which need they need unchecking, other places make it so you have to check a box to opt out, so you have to be on the ball.
Even on the phone you have to be aware, the second they ask about my details, the first thing I say, and get them to confirm is that it is only for their details, because you can't see any check boxes on a phone, so you need to assume they do have such check boxes, and make sure they are aware of your feelings before giving them anything, none of this is a guarantee you will never get spam again, but it will be a big help in stopping it from starting, hope this helps.
