Comments #1 and #3 are based on confusion and disinformation from denialists. There are several good sources of information available on the web; one is http://www.skepticalscience.com/argument.php (where you can find responses to all the above claims).

1. The fact that 1998 was unusually hot does nothing to change the overall trend of temperature increases. It's a simple misunderstanding of the basic science to suggest otherwise.

2. 1934 is the warmest year only for the United States, which is a rather small part of the globe. This again does nothing to undermine the fact of global warming. Fluctuations are to be expected; it's irrational to focus on them when one is trying to establish overall trends.

Beware of denialists who cherry-pick facts to try to obscure a thoroughly convincing body of scientific evidence. It's the same strategy that Big Tobacco used, that creationists use to deny evolution, that crazies use to deny that HIV is the cause of AIDS, etc. etc.