About the comic,i think he's not dead.It was just a Halloween prank or something.If he was dead,you would not even live to see The Garfield Movie or even its sequel.
Apparently, you did not put much thought into the final saying if you think it was a Halloween prank.
If you read what people are analyzing from it, he's playing today's situations in his head, even though it's not happening.
However, see my response to Azuremen, below.
I think this strip was written more to make people appreciate what they have. As you don't fully realize the value of something till you no longer have it.
Fairly depressing though, but happy ending it looks like (Or I missed something)
Exactly.
I believe Jim Davis decided one week to set Garfield into an alternate world where Garfield has been dead and uses the death of Garfield as way of expressing what Davis wants us all to realize. Afterwards, Garfield continues as it was 2 weeks before. It wasn't really the Garfield we all think of, just a 1 time thing in life to remind us with the help of a Comic Strip to realize, as Azuremen said, to appreciate what we have.
In the world that is Garfield, he is alive and fine as every other Comic Strip character. This situation though was one of the more unique ways of comic artists expressing an idea. Throughout time, everyone will occasionally see an artist use his comic strip to portray a message to us that is sometimes different from what we're used to reading. In this case, it was done by the "death" of Garfield.
It's a fantastic idea, imo, as it shows if you grasped what Davis said. If you're relying more on the fact that Garfield "died", then you didn't read deep enough into the strip. It's not about the death of Garfield, it's about the message we should all look at.