Hi FF2005,
There are definite scriptural problems with the quote from the WT:
"Conclusion of the system of things" does not equate with "the last days." See this post (off site) that surveys each occurrence of the phrase. The phrase equates better with the start of judgment day or "the day of the Lord."
On the phrase, "last days," this post (also off site) has links showing that NT writers viewed Jesus' 1st advent as the beginning of the last days. 2Ti 3:1-5 is a good example. When you look at the ensuing context (2Ti 3:6-9) it is clear that Paul included his time within "the last days."
Heb 1:2 shows that Jesus' 1st advent was viewed as the beginning of the "last days." - In all translations except the NWT. They don't want the last days to begin then. It would mess with their 1914 & 1919 doctrines.
Also compare Paul's reasoning in Acts 17:30-31. In Paul's view, Jesus' resurrection changes how God is dealing with mankind. Prior to that He lets mankind go about as they wish. But since then He is trying to coax "all mankind, everywhere" to repent.This view argues that Paul saw the time since Jesus' 1st advent as a final age before judgment day. And this view compares well with Heb 9:26-28.
Prior to 1914 God was calling on 'all mankind' to repent. And it continued to be that way after 1914. 1914 changed nothing - nothing, that is, from God's standpoint. The WT's position on "the last days" is arguably anti-christian, anti NT.