Since your aunt was the first to die and she left a will (leaving everything to your uncle) then her estate is irrelevant, as it has already been bequeathed in total.
Assuming your uncle's will left everything to your aunt (who pre-deceased him) he effectively dies �intestate� (that is, without a will). So the rules of intestacy kick in, but are applicable only to your uncle�s estate.
A quick look here:
http://www.cch-solicitors.com/wills/intest.htm
will explain those rules.
Assuming your uncle had no living children or parents, it is likely that his brothers and sisters will inherit.
By virtue of the fact that your aunt died first (leaving her estate to your uncle) it looks like you are ruled out.