It sounds like you need to combine a few conditionals to make this happen. If they are "either/or" kinds of scenarios (i.e.. display here OR here) then you can just create two conditionals and then assign both of them to your Custom Widget Area or Hook Box. But if they are "this AND that" kinds of scenarios then you'd need to do that inside a single Custom Conditional (i.e.. display here AND here). The latter requires the use of the && code separating your two conditional tags like so:
is_archive() && !is_category()
(&& = and / ! = not) So the above conditional set would say "display on archive pages, but not category archive pages" and you would type this kind of combo inside the same Custom Conditional tag area.
Note that I'm not sure exactly what combination you need here because I'm still not 100% clear what you're going for, but if you're still having trouble just clarify a bit more on your reply and I'll see what I can come up with. It sounds like you want your Widget Area to display on your main blog page and your single post pages as well, but as I said I'm not very clear at on that.