Okay I think that it is time for me to join this debate and say that, depending on what type of thanos they are up against determines the outcome. ReiKai is describing the top Thanos who is above the DC gods in some respects, however the reason why this leads to big debates is because, goku ssj3 is arguably a match for superman who thumps darkseid, yet many believe darkseid to be superior to thanos. This causes one to think, well hang on a minute, if guys like superman can take out darkseid, goku should be ablte to take on the likes of Thanos.
However there are certain factors that need to be addressed:
Speed: Thanos will not just get speedblitzed (the one ReiKai is talking about), if it is just straight at him (as SS usually does), however, what ReiKai is failing to see is that even in DBZ that is not a valid move, just look at Krillin vs Nappa fight. When he charges at Nappa, at the last second he changed direction, and it caught Nappa by surpirse. This is very common in DBZ, never go head on, in fact it was why gohan was unsuccessful against Dabura. In fact DBZ fighters are experts at quickly changing direction. Examples include goku dodging freiza's attack whilst in that sphere, plus the whole Cell vs goku battle.
Magical abilities: Thanos makes SS look like childs play, yet even Majin Buu who could destroy the universe with his magical Ki, could not absorb Vegetto (some claim the Kai's helped, but I have not to this day found out where they got that idea). (I know that these are movies), but goku was able to go up against reality warper Janemba and also slay Hirudegarn. I have no idea how goku would fair when materialised into an inanimate object, but I know Vegetto still kicks butt (lol). I also don't know whether they would escape or survive a black hole. What I do know is that reality warper and matter manipulators did not even attempt it, as if it would be fruitless.
Strength: Thanos has god-like strength, pimp slapped up silver surfer, and so is not one to charge head on against. But DBZ moving at insane speeds, and experts in martial arts always have their backs covered, in the sense that they are already insanely strong, goku lifted isometrically 40 tons in base form (struggling), ssj3 is 200 times more powerful, meaning that goku could lift about 8000 tons max. Vegeta would be about 4000 tons, as ssj2 is 100 times more powerful than baseform. Vegetto's power is basically goku's strength times Vegeta's which is: 32 million tons. This is clearly below the likes of Thanos. However that is pure lifting power. There punching power would be greatly increased by speed and technique. Speed pulses in dragonballz: goku dodged tien's solar flare which is light, and he was a kid. Therefore DBZ strength is not to be laughed at.
Clearly Thanos is outclassed in this area, goku has displayed the ability to within seconds know an opponents techniques and all its flaws, plus mimic it in an even better form.
Blast power: Goku is definetely greater than a solarsystem buster, as Cell's kamehameha wave was solar system busting power. King Vegeta had a power level approximately 10000 and destroyed 3 planets with one blast in a canon movie special. Vegetto is surely greater than a galaxy buster because the energy required to blow up a solar system squared is greater than that required for a galaxy. However, Thanos is very powerful.
There are many other things, I think that the team wins this, but this is heavily due to the use of the extremes of both sides. If you feel that I am underestimating Thanos please inform me of what I am missing out.