I don't know if this question has already been covered, but I'll ask anyways.
What if Sam had been given the ring instead of Frodo? How would that have changed the plot?
You see a little bit of that when (spoiler) Sam gets the ring for that time. Do you think he would have just cast it into the Cracks of Doom if he had had it as long as Frodo? I'm still debating on this.
Long, long ago when we still used the PT email discussion thingy, several of us debated this exact issue... we never did come to any conclusion
I think it depends on your opinion of Sam. As you may or may nor know, we have a number of ardent Samwise haters around here. Fortunately, I am not one of them!
I think Sam might have made a better ringbearer than Frodo. The reasons for this are complicated... in a nutshell, I think Sam, being just a tad "simple" was slightly more immune to the effects of the Ring than Frodo.
If you recall, Sam gave up the Ring to Frodo in Cirith Ungol with only the slightest hesitation. Up to this point, Bilbo had been the only being to ever willingly give up the Ring... and then only with some heavy prodding from Gandalf.
Now, you may say, "Well, Sam only had the Ring for a very, very short period of time relative to Bilbo or even Frodo, for that matter." But if you consider the fact that Gandalf refused to even touch it for a split second then you could come to the conclusion that for most beings, a split second is long enough.
I think Sam showed extraordinary resistance to the power of the Ring. And though I can't say for certain that he would have been strong enough to do what Frodo couldn't, I do think he would have been more likely to do so than Frodo. Does that make any sense?