If my alternative is Billary 2.0, Uh, uh, uh Obama or Also ran 2004 Edwards, you can bet I would vote for President Bush a second time (to young in 2000).
However, the question is flawed in two respects. First-as has previously been pointed out-a vote for a canidate is sometimes a vote against another. Second, if term limits did not apply a President's second term would look alot like the first-they would be trying to get re-elected about a week after taking office.
I think that immigration reform would have looked a lot different, the war would have been re-evaluated and strategy adjusted sooner and a host of other topics would have been steered more toward the middle of the road. So, if eligable for a third term, the second term would have looked a lot different.