Hi Lal,
Under the sub-heading The Four Noble Truths you state that suffering and the truth about suffering is two different things.
How I see the distinction between suffering and the truth about suffering is that, the truth about suffering refers to a mind made thing and therefore something that can be got rid of permanently. So here suffering can include bodily pain but this is not part of the truth about suffering.
When the Buddha attained enlightenment, he got rid of suffering permanently at that point. However, he did feel bodily pain, got sick and eventually died. So obviously the bodily pain, getting sick and dying is not the suffering he was referring to as the truth about suffering. So, I think the truth about suffering refers to the mind made suffering (the lamentation) that is experienced together with pain and sickness.
If we actually think about most of the suffering we experience it has nothing to do with any real tangible pain. (By suffering here, I mean sorrow, sadness, stress, depression and all those related synonyms). So, when contemplating on this it can be seen that the truth about suffering, is simply a mind made concept that we can get rid of.
This is the same for the happiness and elation we experience as well. It is mostly a mind made concept and not anything tangible. That is why, something that makes one happy may not have any effect on another. (I think this is explained well on the site).
Of course, by attaining nibbana, one will also end the bodily pain in future lives as well. So you do eliminate the potential future suffering as well.
The post also states; Understanding the truth about suffering requires an understanding of the wider world of 31 realms, and that most of that future suffering would be in the four realms or the apāyas (of which animal realm is one).
By looking at suffering the way I have explained earlier one may not even need an understanding of the wider world of 31 realms to understand the truth about suffering to a certain extent. If one must believe in the 31 realms to see the truth about suffering it may not be very practical. Because if it were the case then we would need to try and prove the existence of such realms without any doubt before getting along on the path.
I for one, am not 100% certain that there are such realms. However, I am very open to such a possibility. And I tend to believe in it based on the fact that it is part of a very comprehensive (no holes) theory, of which I have not been able to disprove any aspect of the theory yet.
So, what I am trying to say is that understanding of the 31 realms may not have to be a pre-requisite to understand the truth about suffering. I think this is explained on the site, but just by looking at this post it can be a bit misleading.
Akvan