The OP raised this with us today and I replied with the following:
Unfortunately, that isn't how the allocation works. Some could argue that 250MB "web" space is for an amount of space for your account hosted on the "web".
The amount is collective, so if you do find that you need more space, you would need switch to a shared hosting account. If you had 250MB of files and then received an email, it would be queued until you had enough space, up to 7 days before being returned to the sender.
I will however look at modifying that page to give greater clarity as it is the first time anyone has queried the term.
We regard web space as the entire space allocated to an account to be used however the account holder wants. It could be used all for files, or even emails.
What people define as "web space" varies* so we have changed the text slightly to indicate it is for both so there is no further confusion.
regard web space to include emails too.