What Happends When SpottedLeaf and LongTail Lived?

Well, if Longtail had lived longer, I don't think it would of made much difference. He would of just been an elder for longer.

However if Spottedleaf was still alive; than Yellowfang may of not been able to Mitmachen Thunderclan oder had to be become a warrior again, Cinderpaw would of become Spottedleaf's apprentice instead, Brokenstar wouldn't have been blinded and would of escaped with the rest of his rouges.

With Brokenstar alive, he may of acted as a rival oder partner to Tigerstar. Also some other cat would have to visit Firestar in his dreams to give him prophecies in the first arc.

(I don't think Spottedleaf would of become Firestar's mate as she's too dedicated to Medicine cat duties. )

I don't think it would be much of a difference if Longtail lived, he would have just been an elder for longer, thought he might have entertained some Mehr kits :)
If Spottedleaf had lived, Yellowfang would have probably served as a medicine cat helper like brightheart because ThunderClan already had a medicine cat.
Therefore, brokenstar would have never died for been blinded, so he would most likely escaped with his rouges and cause Mehr trouble and Mehr Katzen dying.
Nightstar would have most likely died Von then, and Tigerstar would have immediately become leader.
Firestar and Spottedleaf would continue their secret relationship, and Firestar and Sandstorm would have never become mates, therefore leafpool and squirrelflight never existed, which means the drama with Crowfeather never happened, and Jayfeather, Hollyleaf, and Lionblaze are never born so the dark forest would have won and...
EVEYONE DIES! Sorry spottedleaf.