WP can’t access outside sites

I’m fairly new to WordPress 2.0 which I am hosting on my server provider aplus.net. Whenever I have a plugin than needs to access another site for some of its function (like tags, translate, you tube embeds, etc) I am finding that NONE of them work.

I think I have narrowed it down thanks to info in the forum and codex, to some sort of problem with possibly a port not being open by my provider. But I do not know which port that is or what to request of them. They will open ports if I request, but I do not know what to request! Of course I could be completely off track here too. I am very new to this side of things so any help would be greatly appreciated!