Correct me if I'm wrong, but is the SRP anti-Israeli (hatred based upon a conspiracy of American support to Israel and hatred to America)?
They indeed do no agree with the American anti-Serb policy.
They are not anti-Israel neither pro-Israel.
They are focused on the problems with the surrounding nations of Serbia.
Serbia does not even border with Israel, let alone that there exist any territorial issues between those two states. So Israel is not a priority. Be sure that there does not exist a reason for the Serbian Radical Party to be anti-Israel.
was it Seselj who visited Sadam's Iraq?
Yes because Seselj saw in Sadam a tool which can ensure the international stability. Sadam was crazy enough to attack Iran. With Sadam in charge in Iraq, Iran would have its own problems. In that case Iran would not pay to much attention to the Balkan conflicts, in which also Muslims are involved.
Sadam was necessary to keep Iran outside the conflicts.