135z is very deep, but not (AFAIK) unnaturally so, especially if you've embarked on a high-elevation area (like a mountain) and have all three cavern layers enabled.
Keep in mind that the distance between z-levels is identical to the distance between tiles in the x and y directions, meaning that a dwarf going down 135z is going no farther (i.e. taking no longer) than one traveling 135x or y. Which is still an appreciable distance, though probably not as bad as it seems. Still, it wouldn't be my first choice to have dwarves walk all that way, especially carrying heavy stuff like ore.
Now, if you had ore and metal bar stockpiles near the magma, and linked those to the forges, you'd save your smelters and smiths the long haul - you could essentially create a "mini-fort" just for metalworkers down there. Other dwarves would still haul ore down and finished goods up, which would take a while, but using wheelbarrows would cut the time considerably. So I think that's feasible, if not the most efficient (or "dwarfy") solution.
Getting magma up to the existing fort would be the best outcome, but it'd be trickier.
I would never in a million years build a 135z magma pump stack, especially not as a newer player. It'd take way too many resources and a lot of power (which, admittedly, isn't that hard to get if you have a stream). But pump stacks are also difficult to set up, as they require some precision engineering. Highest I've pumped is ~40z, and that was a pain.
The other option is minecarts, which is a lot easier but requires some tedious management. Dump some (magma-safe) carts in a small, sealable chamber, then flood it with magma - it'll fill the carts, each of which holds 2/7 depth magma (you need at least 4/7 to operate a smelter or forge). Then drain the magma and unseal the room and let your dwarves take the carts up to your forge area (don't worry, they won't burn their hands). You can set up track stops adjacent to the pits where you want to dump the magma (make sure the stop is set to dump in the right direction!), then make routes that include those stops and assign the magma-filled carts to the route. As soon as the dwarf bring the cart to the stop he'll dump it. I know that sounds really complicated, but it's actually pretty easy once you figure out what buttons to press (and you should read the wiki about minecarts, track stops, and routes).
You can apparently automate the minecart process with tracks and routes, but you don't need to - once you have your 4/7 magma pits you're set for life.
So I say: minecarts if you're bold (expect a few dwarves to get fried - such is life), or mini-fort for metalsmiths if you just want something basically functional.
And yeah, snakes (and other legless creatures, like carp) "standing up" is normal - just a quirk of the way DF understands "standing" and "lying down".