Do you think it is likely that all denominations contain the fundamental teachings for salvation, and all the other details that Christians can't come to an agreement about are irrelevant?
I would not say that
all denominations "contain the fundamental teachings for salvation." Some don't even consider
salvation an important subject anymore.
Disagreements among different groups of believers are not irrelevant, although they may be secondary. As a credobaptist, I cannot fully commune with a paedobaptist, even though I may agree with much of his theology, and have some limited communion. The truth is that I have more in common with a conservative Presbyterianism than with the Disciples of Christ, even though my views on baptism and church governance are more aligned with the Disciples than with the Presbyterians.
If so, do you think all the constant quarrel and division within The Body Of Christ, that has been going on since the Catholic and the Orthodox Churches separated in 1054, is displeasing to God?
First, schisms long predate 1054, which is a convenient way of dating a division that had been proceeding for centuries. Donatism held sway over large parts of Christendom. Much of Western Europe (under the barbarian kings) and even Byzantium espoused Arianism; it's probable that Arian Christian outnumbered Trinitarians. Even in the New Testament you can find schismatics.
Is God displeased by the fractures within the Body of Christ? In some ways I think so. We often elevate secondary matters to items of prime importance and are willing not only to disagree but to virtually condemn to hell those with whom we disagree.
On the other hand, to insist upon conformance to a single standard of practice is to ignore the benefits of diversity. Spurgeon doubted that a single faith group could have developed the variety of (beneficial) practices he saw in the evangelical churches of his day.
There are divisions even with churches that are unresolved and need not be. I am an Augustinian in soteriology, I would prefer a more liturgical service, and I would prefer more hymns. At an early age I discarded the
Left Behind, Hal Lindsey nonsense that has become the default eschatology of so many Baptist churches. Yet here I am in a church in which I am in a distinct minority on all these things. There is room for diversity within the congregation and without.