I'm just wondering, with Nibbler being there and Fry also under the desk; and then the other Fry in the cryo-tube and all the Benders: Can someone please create a timeline of what happened that night please?
Here is a very shoddily-produced timeline of the events of that night. Bear in mind, there will be tonnes of spoilers below, so don't read it unless you've seen all four seasons of the first run of Futurama and the first movie, Bender's Big Score.
Nibbler makes crank phone call to Panucci's Pizza, prompting Fry to visit.
Fry from Year 1999 shows up to deliver pizza and sits in chair, with Nibbler hiding under table.
(original timeline) Nibbler pushes Fry into freezer (original timeline superseded after this).
(1st alternate timeline from Episode 4.10, The Why of Fry) Fry from Year 3004 shows up underneath table, argues with Nibbler before Nibbler pushes Fry from Year 1999 into freezer, then Fry from Year 3004 pushes Fry from Year 1999 into freezer.
(1st alternate timeline) Bender shows up from Year 3007 to kill Fry from that same year, drinks too much beer, needs to urinate, activates time-code (1st alternate timeline is superseded after this).
(2nd alternate timeline begins during Bender's Big Score) Bender from year 3007 is waiting for Fry from the same year to show up in the past, meets self travelling back in time from two-minutes later, who tells him to wait for Fry. This creates a time-travel duplicate, Bender from the 1st alternate being the original Bender, with the Bender from the 2nd alternate timeline being the doomed time-travel duplicate.
(2nd alternate timeline) Fry from Year 3007 shows up, pushes duplicate Bender into freezer.
(2nd alternate timeline) Fry from Year 3007 visits Panucci's Pizza, realises he can't buy any pizza due to not having any money in the correct tender, goes back to the cryogenic's lab to eat the pizza he left there. Takes a bite of the pizza, realises it's cold, uses the time-code to travel back in time to one hour in the past, when the pizza was warm. (2nd alternative timeline is superseded from this point).
(3rd alternate timeline begins during Bender's Big Score) Fry from Year 3007 shoves duplicate Bender in the freezer, runs into Fry from an hour in the future. This creates a time-travel duplicate, with the Fry from the 2nd alternate timeline being the original and the Fry from the 3rd alternate timeline being the doomed time-travel duplicate (Lars Fillmore). The two Frys argue over the use of the time-code, with duplicate Fry leaving the cryogenics lab.
(3rd alternate timeline) Original Fry opens freezer to get Year 1999 Fry's wallet, accidentally falls into the freezer behind him.
(3rd alternate timeline) Duplicate Fry visits Panucci's Pizza, asks Mr Panucci if he can move in to the upstairs room, begins new life in 21st century until he dies during the events of Bender's Big Score.
Hope that helps. I'm sure there's someone out there who can make the same timeline in considerably better format than I can, with my borderline-illiteracy in internet matters.