TL,
There is a huge difference between foreknowledge, prescience, foresight, etc. in the Pelagian, semi-Pelagian and Arminian (and JW) soteriologies and predestination in the Augustinian-Calvinist tradition. The former does not imply causality, while the latter does. In the former God only knows what individuals will do by their own free will; in the latter he himself causes the individual's response.
I'd just highlight your quotation:
God's choice of certain individuals unto salvation before the foundation of the world was based upon His foreseeing that they would respond to His call. He selected only those whom He knew would of themselves freely believe the gospel. Election therefore was determined by or conditioned upon what man would do. The faith which God foresaw and upon which He based His choice was not given to the sinner by God (it was not created by the regenerating power of the Holy Spirit) but resulted solely from man's will. It was left entirely up to man as to who would believe and therefore as to who would be elected unto salvation. God chose those whom He knew would, of their own free will, choose Christ. Thus the sinner's choice of Christ, not God's choice of the sinner, is the ultimate cause of salvation.
This is exactly what JWs believe as to the process of salvation for both of their "classes". In both cases everything rests on the free will of the individual and his undetermined (even if foreseen) response to the Gospel.
As to your other question, I can't think of anything really comparable to the current (Rutherfordian) "two-classes" / "two-hopes" WT soteriology. However you must consider its evolution from Russell's teachings. To Russell, the "second class" was not made up of Christians in the present age, but of non-Christians who would be resurrected in the millenium. Russell's idea was one answer among many to the age-old question, are all non-Christians lost? Many responses have been offered to this question throughout Christian history, from the ultra-strict view of Cyprian, "no salvation out of the church" to the universalistic view of Origen, his apocatastasis theory in which all, even the devil, would eventually be saved. Intermediate views involve a final judgement of people's deeds by their own conscience, which is revealed as an relationship to Christ although the individuals did not know it as such (so, differently, Matthew 25 and Romans 2). So the belief in Christ as the unique way of salvation can be reconciled with salvation of non-Christians -- only they didn't know they were Christians (cf. Karl Rahner's concept of "anonymous Christians"). The originality of Russell's answer is to posit a time (the millenium) when former non-Christians can consciously choose salvation through Christ, instead of the classical view of resurrection and judgement based exclusively on people's deeds prior to their death. Such a theory may have been found in other Christian (adventist?) groups, I'm not sure about that. But this is a completely different thing which Rutherford made up with his doctrine of two classes of Christians in the present age. This theory does not serve a wider salvation, only the practical submission of one class to another.
