Maybe I can try and simplify. You’re Jewish, so you are broadly divided into Conservative, Orthodox and Reform Judaism. Your Orthodox Judaism is nothing like Orthodox Christianity, so get that out of your mind now. Orthodox Judaism probably has more in common with maybe Fundamentalist Christianity where everyone else is screwed up and they’ve got it going on rather than Orthodox Christianity which mostly doesn’t concern itself with what other groups are doing.
Orthodox Christianity… (actually, I’m going to digress a bit. Orthodox Christianity itself has two broad divisions - Oriental Orthodox (mostly practiced in the Middle East) and Eastern Orthodox(mostly practiced in Eastern Europe and the Caucasus). We’ll concern ourselves mostly with the latter.)…anyway Orthodox Christianity is in many ways like Judaism as a whole. It tends to be very culturally based. If you’re Russian, you go to the Russian Orthodox Church and your 'leader 'is the Patriarch of Moscow (who sorta kinda answers to the Patriarch of Constantinople as all Eastern Orthodox churches do, but it really functions more like a council of bishops who get together and figure things out). If you’re Greek, you go to the Greek Orthodox Church and your leader is the Patriarch of Constantinople so the churches are very much ethnically based (This is not a requirement though, anyone is welcome to go to a Russian Orthodox Church, but it’s rare for non-Russians to be there.) They are in full communion with the Catholic Church. What that basically means is that both groups recognize the other as full and complete expressions of Christianity. It doesn’t mean they are the same though. An analogy might sorta be the way Conservative Jews feel about Orthodox Jews. “They’re different, but they’re still following a valid form of Judaism.” In a similar way, Catholics feel that Protestants have made serious breaks with Christianity, perhaps analogous to how Conservative Jews feel about Reformed Jews.
In liturgy (the way in which they hold their services) Orthodox Churches are ‘High Churches’ This refers to a very formal liturgy (sometimes called ‘smells and bells’ by the more jovial among us - as an aside, you can tell I’m Methodist which comes from the Anglican tradition, since I just noticed I tend to use their terminology) What it really means is that their services tend to be sort of ‘set in stone’ and involve a great deal of traditional religious practice and imagery. It’s kind of hard to analogize with Jewish services, but think of Evangelical Protestants kind of having services like Reformed Jews while Catholics and Orthodox are closer to Conservative Jews. To get into all of the exact differences in liturgy would require a book and not a board post, but suffice it to say that even though Catholics and Orthodox Churches are ‘high churches’, this doesn’t mean that their services look alike. They don’t. Pre-“Vatican II” (a conference that the Catholics held in the early 1960s that significantly changed Catholic liturgy) Catholics might have a bit more in common with Orthodox liturgy, but post-Vatican II things have changed quite a bit.
As a Western Christian, I would say that mostly Orthodox Christianity isn’t thought of at all. It’s a small religion in the West, so we don’t think about it much at all except to broadly think “It’s nice that they are Christians too.” When we do think about Orthodox Christianity, we almost immediately think of two things. How their priests look and iconography. Their priests dress all in black with tall hats (a lot of the time anyway) and they look like dwarves (being facetious, but they are known for having very long beards. They actually look pretty cool.) That’s different than most forms of Western Christianity, so it stands out. We also think of their icons which to us are very pretty pictures of saints and angels and the like. In the Eastern Orthodox Churches though they are stand-ins for Christ or the saints themselves and the paintings have very specific attributes that are required to represent the person they are representing. This is weird to Western Christians (to Catholics a bit less so than to Protestants, but even Catholics probably think that Orthodox take it too far.) and quite a few Protestants would almost certainly say idolatrous, but like I said, we don’t tend to think of the Orthodox churches much at all and those types of Protestants are too busy screaming about crucifixes to bother delving into Eastern Orthodox beliefs. The only other thing that MIGHT cross our minds is their fasting tradition which is shall we say ‘intense.’ Orthodox Christians that completely follow their fasting schedule end up fasting over half of the year. Now, it should be said that not a whole lot of them actually do, but they’re supposed to if they are completely following recommendations of the faith.
I don’t know if I made it easier for you to understand or harder, Christian divisions usually come down to fundamental differences in how we think about God and our relationship to him, and Orthodoxy is no different in that regard than any of the other 30 thousand denominations floating about. Getting into real theological differences though could be very difficult for a non-Christian to understand without a great deal of reading, so I tried to stay more on the visible side of things.