1. In a few books I have read based on Vaishnavite teachings it is said that in Buddhism a soul is not said to exist is this true ?...But if an eternal soul does not exist then what is it that dies and is reborn again and what is the ultimate fate of all sentient-beings ?
You could say "Soul" is not a permanent self. Using the term exist, the soul can't exist with in Samsara unless it has a host ( body ) .
So Buddhist definition of soul does not exist.
I think Buddhist texts call it Conscience continum .
Fate of all beings trapped in Samsara is Birth, Aging, sickness, Death rebirth.
even the state of "Infinite death" is Samsara bound, and therefore follows the laws of Rebirth.
Even the state of "Infinite Life" or something like the heavenly realms IE reborn as a Deva, will not last forever and still bound by laws of Samsara .
Nirvana is not bound by Samsara, Notions like everlasting Life, never ending Death are not Nirvana .
in Human Language we call it Permanent Bliss free from Samsara etc.
2. Someone I met once commented that how he thinks that Buddhism seems to be a more escapist approach to life and he comments on how we should not cease to desire because ceasing to desire would be denying our humanity and to deny our humanity would be to reject life itself. How would I contend with this view ?
Buddhism is far from an escapist approach .
More less you could contend with this view by saying Buddhism in regards to Humanity is about what needs to be done rather then what one wants to be done with it.
all Humans need food, shelter, water, clothes needed for maintaining their lively hood, Beliefs
a lot of Humans Want, Best food $ can buy, best water $ can buy, Best clothes $ can buy, Best cars $ can buy, Biggest House $ can buy, lots of other wants like a star named after them etc.
The pleasures of our world will bring temporary joy but it will pass, this does not mean if someone bought you idk a ferarri you would reject it coz its not needed. accept it and maybe sell it to get a cheaper car and use some of the cash to help someone in need etc.
3. Does a Buddha cease to accumulate all karma ? I once read how in Jainism a siddha (liberated one) will not help a suffering being because he has gone beyond all desires
Buddha's stop accumulating Karma, their liberated and free from it.
That siddha prolly just didn't see any need to help anyone . Prolly they were thinking, everything they need to be Enlightened was right in front of them, their price they pay for not seeking it out . Maybe next life they will .
An Enlightened Buddhist vs an enlightened Jain are most likely gonna have a different thought process so to speak.
From what i read on Jainism few yrs back.
Jainism ,they pull out their hair with their hands to conquer pain.
they won't walk on grass ( something like that) so they won't kill insects.
They won't eat certain kinds of Veggies .
, they won't eat seeds ( that 1 seed they eat could of gave life to 100 more )
some Jains don't brush their teeth due to killing innocent bacteria
they only have sex when they are trying to conceive a child, due to millions of sperm lose their life .
Where as Buddhist teachings *MIGHT* say a lot of the stuff on Jainism is considered an Extreme .
Jainism might say how can one be extremely compassionate in regards to killing .
Both Mahavira & Gautema Buddha attained Enlightenment .
btw mate i mentioned the soul due to your Jain references in the thread.