Cheezy the Wiz
Socialist In A Hurry
Just some petty sniping and nonsense. 
Well I suggested it was possible, depending on the timing and circumstances.
A major problem was the Stalin lackeys in charge of the Army during that time, principally Voroshilov. There are few people in Soviet history I hate more than Klement Voroshilov; every thing he touched failed, and he stank of boot-licking and arrogance. Timoshenko wasn't really a poodle, but he wasn't a great high-command guy, and he was one of the few that Stalin trusted before Zhukov proved himself at Leningrad. But even putting him in charge was a huge gamble, and he wasn't without his screwups.
I really don't think so.
The bigger problem was his horrid supply lines. He stopped at El-Alamein primarily because his supplies had to come over land on rickety dirt roads from Tunisia.
This was the only purpose of the Soviets ever proposing the idea in the first place.
This had been the understanding since 1924, and was the major driving force behind all major developments in the USSR after 1927.

Yes to both questions. Britain alone could have defeated Germany - as Cheezy said, they'd simply starve them out - let alone with US help, and Russia was much stronger than Nazi Germany. Its economy also wasn't crumbling, unlike Germany's.
Well I suggested it was possible, depending on the timing and circumstances.
As other people have already said though, the main question is one of timing. Germany damn near defeated Russia simply because of Russia's incredibly piss-poor defensive efforts in the months following Barbarossa, until Zhukov and others began to get their act together.
A major problem was the Stalin lackeys in charge of the Army during that time, principally Voroshilov. There are few people in Soviet history I hate more than Klement Voroshilov; every thing he touched failed, and he stank of boot-licking and arrogance. Timoshenko wasn't really a poodle, but he wasn't a great high-command guy, and he was one of the few that Stalin trusted before Zhukov proved himself at Leningrad. But even putting him in charge was a huge gamble, and he wasn't without his screwups.
If Germany hadn't made some of its rather large mistakes in the Eastern Front, they may actually have pulled out a victory there, though it's doubtful.
I really don't think so.
There's also the question of how the Allies would go about invading Continental Europe without Soviet help. Presumably through North Africa, but a Germany without a Soviet threat to its East may well have flooded troops into French North Africa to forestall such a move. Despite common belief, Erwin Rommel could never have conquered Egypt no matter how many troops and supplies he was given, because El Alamein was impassable.
The bigger problem was his horrid supply lines. He stopped at El-Alamein primarily because his supplies had to come over land on rickety dirt roads from Tunisia.
A more interesting counter-factual is what would happen if the USSR joined the Axis, as once seemed likely? As a willing and equal partner, not merely to buy time to prepare itself for war?
This was the only purpose of the Soviets ever proposing the idea in the first place.
That is the only realistic situation in which Hitler would not still keep numerous forces along the Soviet frontier to forestall an invasion, even if Operation: Barbarossa never went head. Leaving the German-Soviet frontier undefended would be an invitation for a preemptive strike by Stalin, who had to know that he would be on Germany's hit-list eventually.
This had been the understanding since 1924, and was the major driving force behind all major developments in the USSR after 1927.