It depends on what you're after. I find it really interesting that each country has it's own identifyable style, you can pretty much hear a band and know where they're from.
American bands tend to be more technical, with lots of complex riffs, whereas English bands go for a more chord based approach, with a dose of melody. Scandinavian bands tend to take a more melodic approach. This is the same for classical music though, the musicians from the US have better technique, those from Europe tend to have more feeling (this isn't a criticism of either side though, just an observation).
In regards to Black metal, I'd say no to your question. I think the lack of overt emotion in American music (I don't mean the musicians aren't feeling it, it's to do with song construction and approach) inhibits their efforts (name 5 american BM bands- the only one I can think of is Ancient, and they were fronted by a Norwegian), which is also true in regards to Doom (exceptions here also (such as Morgion), but compare it as a whole to their British and European counterparts). There are some ok english BM bands, so too other countries, but the bulk of the good stuff comes from Norway and Sweden.
In regards to death metal, this is more open to personal taste (IMHO, as I see the pool of top-notch BM bands as being quite small, whereas by comparison, the pool of really good DM bands is large). I mean, Death and Deicide are obviously American, they could come from nowhere else. Bolt Thrower and Napalm Death could not be mistaken as coming from anywhere other than the UK. And we are all (over-)familiar with the whole Gothenburg sound etc... So it really depends on what you class as good death metal, I like them all and don't see any one region as having a definite advantage.
Disclaimer: yes, this post is full of generalisations, and there are exceptions to everything, but hopefully you get my point 
