You are doing that now. You say: "I believe that Baptist opinions regarding Christian doctrine are the closest to true." I have no doubt you believe that. But upon what do you measure Truth here?
It is true that no Church has all of the Truth, in the sense that not everything that is true was imparted by Christ. God not only has not revealed all of His Mind to us, we, as finite creatures, couldn't possibly understand it if He did. But it is also true that everything that Christ taught is Truth, and the totality of that teaching is the Deposit of Faith. That discrete, concrete body of teaching from Him, and what was conveyed to the Apostles under inspiration of the Holy Spirit in both Scripture and Sacred Tradition, cannot be in error. It was also entrusted to us with the understanding that it should not be lost to us, and that Jesus would send the Holy Spirit to the Church to preserve that Deposit of Faith, even within the confines of a Church entirely populated by otherwise quite fallible (and forgetful!) human beings. Jesus makes no sense in Matthew 28:20 and John 16:13-15 otherwise.
To the extent, then, that Jesus intended to establish a Church based on teachings of His Truth (and this is confirmed in 1Timothy 3:15), and to preserve that Truth within His Church through all generations to the end of time, one could reasonably infer that it is still possible to find that Deposit of Faith somewhere on earth, intact and entire, in continuous existence from the first Pentecost, when the Church was born, to this day. All one really needs to do, at that point, is find the one Church that has been able to organically trace its lineage of custodianship of the Deposit of Faith back to the beginning.
Obviously, I would say that Church is the Catholic Church. I believe, if nothing else, that that Church alone has much of a claim, based just on historical continuity and sheer existence alone - though, of course, I also believe that its teachings are, in fact, the Deposit of Faith! You, clearly, do not. But you might want to reflect on how the some of the tenets of Baptists do not appear until the 16th Century, and how they do not dovetail with the teachings of "that other Church" in the 2nd, or 7th, or 12th Centuries. No other group besides the One, Holy, Catholic and Apostolic Church has even a demonstrable historical claim to the continuity required. Therefore, since Jesus said He would be with and guide His Church, and send the Holy Spirit to preserve it in the details of the Faith, it would be logical to begin by supposing the only Church with the long-term historical existence necessary to span the entire timeframe involved just might be the Church He founded. If that is true, then it just might be also the case that that Church's teachings are, in fact, preserving the fullness of Revelation - the Deposit of Faith - down to this very day.
That you presently disagree with much of the Catholic Church's teaching is quite understandable, if you simply inherited what you know from another group's perspective. Some folks have a 500 year lineage in that regard! But the true Reference Standard, I would suggest, is not what can only be traced back to the 1500's, or what might have been believed for a few centuries fairly early on, only to have been entirely abandoned until dusted off in our own day. The true Reference Standard belongs to only one Church, continuous in existence and preserved from error, as Christ Himself promised. Disagreement with it, regardless of how sincerely held the beliefs to the contrary, is still, in the end, disagreement with Christ. That the Catholic Church teaches some things contrary to the Baptists' (or any other denomination's) beliefs is not in dispute. What is at issue is whether those other denominations are "correct" to be in such disagreement. And upon what authority of historical continuity can they make a case for their disagreement?
Christianity is defined by the set of beliefs espoused by Christ Himself. To my mind, this is not as dependent on lineage or continuity as it is on faithful interpretation of the Word of God. In short, you’re unlikely to sway my opinion by stating that there was a different Biblical interpretation in 1400AD. In my opinion, the men of 1400AD were just as likely as we are to be wrong in their interpretation. And, tradition can often justify practices that are not otherwise justifiable.
The church established by Christ is the Christian church — in many, if not most, respects, we (Catholic and Protestant) are one church of believers in the divinity of Christ. The lineage of every current Christian denomination can therefore be traced back to Christ Himself.
To the extent that there are legitimate disagreements among Christians as to doctrine, I believe every believer is capable of educated interpretation of the scripture.
Some are certainly more educated than others, and, in that respect, the Vatican is a collection of some of the more educated Christian theologians in the world. Some opinions are certainly worthy of greater respect than others.
As a Baptist, I often listen to the Vatican on theological matters. They are not infallible by any stretch — but they are educated enough to be worthy of consideration (even when I disagree).
SnakeDoc