I believe the Ken Olson quote was that nobody needed a computer in their house, but that was a time where businesses were using terminal servers... it would have been interesting to see where that would have went, but we might be heading that way again since we own nothing and everything is a only a temporary license.
The second quote was "I think there is a world market for maybe five computers", and it's attributed to Thomas Watson of IBM saying it in 1943. The real quote is indeed from Watson, but in 1953, summarizing the sales projections of a specific model of machine, and noting that they actually sold 18 of them.
Gates denies ever saying anything like the 640K quote, but it was possibly someone at Microsoft being salty about the 640K limit that IBM had imposed on the PC through its design.
