Leaders representing various Iraqi opposition groups here are convinced that Iraqi President Saddam Hussein's war with Iran will be his doom, but some do not want him to fall too soon.

Their chief worry is that neither they nor their fellow opposition groups are ready. What with three distinct groupings -- some analysts count four -- sometimes with partially interchangeable memberships, it is little wonder that the more thoughtful leaders are concerned.

"The opposition inside and outside Iraq is not satisfactorily organized," said one leader, suggesting that at least "four or five more months" are necessary to solidify even minimal understandings.

Turning in a restaurant to a table covered with dozens of Arab appetizers, he said: "That is not our problem -- too many dishes and too many groups."

Based in Iran and Syria, the various opposition groups, sometimes in tandem, sometimes separately, are grouping for working relationships well short of the unity that would facilitate their common task. A constantly recurring nightmare is that Hussein could be eliminated before they are ready. Moreover, they have a healthy respect for his ability to remain in power for at least another year.

Mindful of the decade of turmoil and coups that was Iraq's lot after the overthrow of the monarchy in 1958, these leaders fear that without agreement on a minimum program they cannot rule out the possibility that the regime's collapse could lead to large-scale bloodletting and even civil war. Nor, in such an eventuality, are they sanguine about preventing such violence from spilling over to other oil-producing Persian Gulf states.

The major opposition fronts -- the National Islamic Liberation Front, the National Democratic Front and the Majlis Ulema -- were unveiled either just before or after the outbreak of the Iran-Iraq war in September 1980.

The National Democratic Front -- grouping Iraqi Communists in exile, Jalal Talabani's Kurdish Democratic Union and seven smaller parties -- appears to have the official favor of Syria's Baath Party government. But the Damascus authorities also are aiding the National Islamic Liberation Front, a more significant group based here described by one of its leaders as "the strongest of the weak" groupings.

In its ranks is the resurgent Iraqi branch of the Kurdish Democratic Party, led by the late and legendary Mullah Mustafa Barzani's two sons, Idriss and Masud. The Kurdish Democratic Party brought real trouble to Hussein in the early 1970s before the late shah of Iran withdrew crucial support in 1975.

The Brazanis are again active in Iraqi Kurdistan thanks to Iranian arms -- this time provided by Ayatollah Ruhollah Khomeini's regime -- and are credited with having occupied large areas of Iraqi Kurdistan evacuated by Iraqi Army troops sent to fight against Iran farther south.

Other front members are the Shiite Moslem Iraqi Mujahideen led by exile Mohdi Hakim -- said to be the most effective opposition force inside Iraq today -- and dissident soldiers headed by Gen. Hassan Nakib, as well as pro-Syrian Iraqi Baathists and other less prominent personalities.

The Majlis Ulema, or Mullahs' Council, is run from Iran by Mehdi Hakim's brother Bakr, and is staffed by Iraqi ayatollahs strongly influenced by their Iranian counterparts.

The fourth front, active in northern Iraq, groups the Barzanis, their Kurdish ally Mahmoud Osman of the Kurdish Socialist Party and Iraqi Communists, all of whom belong separately to either the National Democratic or the National Islamic Liberation Fronts.

Technically outside these groupings is Dawa, or the Call, the once-powerful Iraqi-based group said to have declined sharply since the Baghdad government last April executed its leader, Ayatollah Bakr Sadr.

The National Democratic Front shows little interest in collaborating with the National Islamic Liberation Front. And so far National Islamic Liberation Front leaders here are not in direct communication with Dawa or the Majlis Ulema. But they note optimistically that the principle of such talks have been accepted and that talks are supposed to take place soon in Iran. Nor have the Moslem Liberation Front leaders established direct communication channels with the Iranian government itself.

In order to attract the widest possible number of Iraqis of all political and religious persuasions, the National Islamic Liberation Front programs calls for parliamentary rule, general elections to decide on the lay or religious nature of the future regime, outlawing of military dictatorship, a liberal economy and "full autonomy" for the Kurds short of partition or independence.

The National Democratic Front platform is a detailed, ani-Western, leftist, socialist economic document.

The physical separation between opposition groups in Syria and Iran is a drawback for coordinating activities, but the opposition believes that is more than offset by sandwiching the Baghdad government in from east and west.

Islamic Front leaders here also expressed concern lest Khomeini and other Iranian Shiite leaders insist that any future Iraqi regime be a carbon copy of Tehran's Islamic revolution.

Iraq is more nearly evenly divided between Shiite and Sunni Moslems than Iran, although some 60 percent of Iraqis are thought to be Shiite.