The story of a "hole to hell" in
Siberia (such as that described in
Voodoo Chile's writeup) can be found on many
Christian fundamentalist websites. It has also been thoroughly
debunked.
Like most urban legends, there is a kernel of truth to this one. There was indeed a Soviet science team that drilled very far into the Earth and encountered some abnormalities. That's pretty much where the truth ends and myth begins.
Far from this event being covered up by the KGB, this is one of the most celebrated scientific achievements in Russian history. The well dug in Kola Peninsula (in 1984, *not* 1989) remains the deepest excavation by man to date. It was, in fact, featured in an article in Scientific American.
Even the more believable details of this story are wrong. The actual depth was 12 kilometers (about 7.5 miles), not miles. The temperature was relatively high - about 180° Fahrenheit - but that's not hot enough to boil water, let alone melt rock.
The rest is just laughable. Even if a camera which could "withstand the heat of Venus" exists, it would have to be rather large and extremely expensive; certainly not the kind of thing you'd lower down a hole in the ground, no matter what you thought you heard. Furthermore, none of those actually involved with the project have claimed to heard or seen anything claimed by this story. Of course, I suppose it's possible that the KGB or some other arm of the Soviet government "encouraged" their silence, but even if that were the case, that regime has been out of power for over a decade. If the people on that project had really seen and heard such horrific things, you'd think they would've come out with it openly by now.
In conclusion, there is no validity to this story whatsoever. Of course, judging by the softlinks, I'd wager most of you guessed that already.
Partial Source: http://www.snopes.com/religion/wellhell.htm
And for a more typical version of this story, go here: http://home.inreach.com/holyfire/Hell