Spanish smoked paprika, pimenton, typically comes in 3 heat levels
dulce (sweet) mild
tradicional or agridulce (bittersweet)
It is probably best to start with a dulce. You can always use other unsmoke chile powders (or hot sauce) to up the heat level.
This is the brand of Hungarian sweet paprika that I recently bought (not smoked
It's appropriate for use in goulash (by the tablespoonfull).
I keep both types in the fridge after opening.
I would not fret about country of origin when it comes to an agricultural product, whether it's paprika, some other spice, olive oil, wine, or anything else. It's like assuming all French Pinot Noirs are better than all of California's. I shop at a store that has paprika (unsmoked) from the US and Hungary in bulk (so you can taste before buying) and find the domestic product clearly superior. And as folks have noted in other posts, the quality of US spice brands can vary, so why assume those in Hungary or other countries does not? So, Erika, Spanish and Hungarian (or US), are interchangeable, so if you can arrange a taste test, let that be your guide.
That said, I must disagree with the other posters who say "smoked" has something to do with different heat levels. Smoked peppers, hot or mild, are called smoked because they are indeed exposed to smoke in the drying process, and the difference in taste is as great as the difference between pancetta (unsmoked) and bacon (smoked). If you smoke a jalapeno you get a chipotle. If you smoke a mild paprika pepper you get a smoked mild paprika, not a hot paprika.
There isn't Hungarian smoked paprika - only, as Bada Bing said, levels of heat. There's sweet (edes) and hot (eros) and a whole range in between. Spanish paprika comes in smoked and unsmoked. For classic Hungarian dishes, I would stick to Hungarian paprika - the Hungarians are quite opinionated about their paprika and I wouldn't want to tangle with a Hungarian unhappy about how you made the paprikas. You can adjust the "heat" of a dish by using more or less hot paprika in addition to or instead of sweet. Spanish smoked paprika is a wonderful addition to not only Spanish dishes but anywhere that you'd like a bit of smoke flavour. I use it in BBQ rubs as well as in paella.
I'll be interested to hear if more expert voices correct me, but my sense is that the Hungarians don't typically market paprika as "smoked"; instead, they array them into heat levels, as one sees with mustards, for example. Spanish paprika comes in smoked and unsmoked varieties. In many recipes, a mid- or low-heat Hungarian paprika could sub for an unsmoked "sweet" Spanish paprika. Smoked paprika is quite distinctive, though, and it's worth going out of your way for in cases where it's called for.
Keep in mind chipotle powder, which would be like a quite hot and smoked paprika.