If You Read X-Men #1, You Don't Need To Read X-Men #2
The second issue of The X-Men is essentially a repeat of the first issue. Instead of Magneto, we get a Magneto clone called The Vanisher who can teleport instead of use magnetism, but otherwise is pretty much just like Magneto - believes in the superiority of mutants over homo-sapiens, threatens the defense of the U.S.A. (instead of taking over a military base, this guy steals the U.S. defense plans and threatens to sell them to 'the commies').
Iceman's corny and annoying antics are even more corny and annoying - if you can believe that. Everyone's powers are still pretty hazily defined (Jean still insists on referring to her telekinesis as 'teleportation'), and there's a couple predictable runs through the Danger Room.
There's nothing new here (except perhaps the introduction of the X-Men's contact in the FBI, Fred Duncan), and a lot of groan-inducing puns and silly uses of Iceman's powers. You'd be best off skipping this issue.