Israel vs Iran war: "Who would win?"- Depends on military strength.

Now Obama can celebrate as he likes to do. First elections win, he was celebrated by the war in Iraq and Afghanistan (though promised to withdraw troops from the first days of the presidency), the Nobel Peace Prize celebrated by bombing of Libya, and now after the second election victory Obama can finally keep the promise to withdraw troops from Iraq or Afghanistan... and enter them to Iran.
Practice of the last war showed that in addition to conventional weapons to prepare the invasion needs a new effective armor with high blast resistance (MRAP). Needed for the war MRAP amount can be purchased by the police formally for combating drug trafficking. For Israel as a U.S. ally, may be needed a formal reason for mobilizing 30,000 reservists. Exacerbation of local conflict in Palestine because of suddenly appeared stocks of weapon well suited. Blaming of Iran for supplying weapons to Hamas is well suited as a reason for the start of intervention.
 Israel vs Iran war 2012: "Who would win?"- Depends on military strength.
Air Force

Israeli Air Force General Dynamics F-16 Fighting Falcon

Boeing F-15E Strike Eagle
On the armament the Israeli Air Force is not much different from U.S. allies.
Typically photographs Israeli planes are easy to find so it is no interesting.

Islamic Republic of Iran Air Force

 In Iran, besides the old MiG-21(and other) is a relatively new American fighters.

Grumman F-14 Tomcat
 Immediately after the end of the Iran–Iraq War, the IRIAF was partially rebuilt through limited purchases of MiG-29 fighters from the Soviet Union.