What do you think about the claim that the solar system belongs to a different galaxy that is headed towards a collision with the Milky Way? It is mentioned on this website among other things
http://www.greatdreams.com/2012.htm
Bunk. The site makes the tiresomely repeated claim that there will be a "crossing point of the Galactic Equator (Equator of the Milky Way) and the Ecliptic (path of the Sun)" in 2012. This simply is not true. The "alignment" is off by several degrees. Also, our solar system is nowhere near the galactic equator, and it will not be there in 2012. Read all about it here and here. Other notable curiosities include the site's use of Jose Arguelles as a reference and outdated claims about the upcoming Solar Max 24 (which is expected to be below average, not "the worst in 50 years").
The Milky Way Galaxy is being approached by the Andromeda Galaxy at a rate of about 100 kilometers per second. Indeed, there might be a "collision" of sorts … in a few billion years.
The author of that page claims Russian people build underground shelters in anticipation for a certain disaster
And I suspect he was quite vague in his mention of this, failing to provide any specifics, context or references. Correct?
and say that ancient people could have predicted 2012 by witnessing an energy burst from the sun causing the sand on the moon to melt and create glass instead.
First of all, how would such an event allow anyone to predict anything about 2012? Secondly, an energy burst from the Sun would not "melt" the Moon. In any event, lunar regolith (soil) is not glass, so the author has some explaining to do if he is claiming otherwise.
Do you think we should disregard him, or does he have a point in saying those things?
I think you can disregard him.
…to match the quote from the bible saying only god knows the exact moment of the apocalypse.
That is not what the Bible says. What it says is this (Matthew 24:36-44):
(36) "No one knows about that day or hour, not even the angels in heaven, nor the Son,[f] but only the Father. (37) As it was in the days of Noah, so it will be at the coming of the Son of Man. (38) For in the days before the flood, people were eating and drinking, marrying and giving in marriage, up to the day Noah entered the ark; (39) and they knew nothing about what would happen until the flood came and took them all away. That is how it will be at the coming of the Son of Man. (40) Two men will be in the field; one will be taken and the other left. (41) Two women will be grinding with a hand mill; one will be taken and the other left.
(42) "Therefore keep watch, because you do not know on what day your Lord will come. (43) But understand this: If the owner of the house had known at what time of night the thief was coming, he would have kept watch and would not have let his house be broken into. (44) So you also must be ready, because the Son of Man will come at an hour when you do not expect him."
It's talking about the Messiah's return, not "the apocalypse." Regardless, various Christians have been declaring the end of days for 2,000 years, and human beings in general have been proclaiming the approach of doomsday for most of recorded history. We're still here.
Could the recent oil spill in the Gulf on Mexico spread to the entire ocean by 2012, thus creating an even bigger ecological disaster, and reducing the amount of the oxygen in the world?
Unlikely, and even if it did, it wouldn't have anything to do with 2012 as discussed on this site.
In addition, Patrick Geryl apparently predicted something like that would happen.
No, he didn't. What Patrick Geryl claims in his book How to Survive 2012 is that monstrous tidal waves will take out oceanic oil rigs, causing oil to spew into the oceans all over the world, all around the same time. It's just an extension of his completely unsubstantiated claims about catastrophic pole reversals and other nonsense. He's a crackpot.
Besides the oil spill, I found a blog entry claiming scientists are about to start drilling into an area that is a candidate for a supervolcanic eruption in 2012. Can you please confirm or disprove this rumor?
http://blog.2012pro.com/2012/super-volcano-risky-drilling-of-the-phlegraean-fields
I assume you're referring to this. The ICDP drills into volcanoes as a matter of routine. It's what they do.
2012 Pro is not a particularly reputable source of information. The site's whole premise — "Scientists agree that we are heading for major changes in 2012," — is a lie. In fact, scientists, at least those who have even bothered to weigh in on this 2012 garbage, overwhelmingly agree on quite the opposite: that there's no reason to suspect any sort of disaster in 2012, beyond the usual numbers we can expect in any given year.