Technically, no. Practically, it may depend on your stance.
This is not a site dedicated to any particular denomination, and since they tend to prefer answer questions, not necessarily about Christianity in general, but regarding doctrinal stances of specific denominations or traditions, your own personal beliefs or even your own denomination's beliefs, shouldn't prevent you from participating.
In my short time here, I have noticed that there is a trend toward questions to, and answers from, Catholic sources. They do generally seem to be preferred, but that may just be speculation.
I think that the current premise of this site favors Catholics in that it is focused to answer questions about denominations from official writings from the denominations. Catholics seem to have the longest tradition of man written, extra-biblical doctrinal stances. There are some other groups, such as LDS or JW, which also have strong traditions of the same, and so it is likewise easier for them to participate, but there seem to be fewer of them who participate, especially of the later. There are many Protestant groups which have long traditions, or at least standard confessions, and so, they do have a somewhat easy time participating.
However, there are those of us who do not have such a written doctrinal stance to reference. I am Independent Fundamental Baptist. We obviously have a history and specific things that we believe, and we do have many authors and publications. Also, in some areas, we're a predominant denomination. Nevertheless, we put a very large emphasis on understanding the Bible and any position taken by any such congregation is considered only as good as the Bible they can give to back it up. There are even groups within the denomination which disagree peacefully on certain stances. The "independent" in the name comes from the fact that we don't believe in having a central authority other than the Bible. IFB seminaries spend maybe a handful of classes which deal with Baptist history and distinctives, and the rest are spent on reading the Bible, learning the core languages, hermaneutics, etc. Since this site prefers to not accept answers from the Bible alone, I still find it hard to participate.
I imagine that if you are non-denominational or perhaps simply somebody who doesn't take a stand on any denomination, that's going to make participation much harder. Such stances are not uncommon, and they are growing. For these groups, you aren't barred from from participating, but you may find fewer opportunities or just have to work harder to join in.
But I'm still new, so there may be some trick I don't know yet, and I'll try to post back here if I learn it.