I've always thought that whatever you want to play should pretty much be fair game. You want to be a dragon PC? Sure. You start at 1st level with one hit point per die. You advance as an elf (4000 xp for level 2). You follow the M/U spell progression table, but you gain a hit point per die every fourth level. I tend to think of dragon PCs as being Silver Dragons because in D&D they are the most fond of humans, but if you want to be red, we can invent reasons why you are playing a good red dragon that enjoys the company of humans, dwarves and elves without eating them or their horses.
I'm not totally flexible. If you want to be a 1st level lich or beholder, I may ask you to think of something else. Then again, if we're playing with characters starting somewhere around 15th level or so, a lich or beholder is not impossible.
In short, play what you want. We, meaning the playing and the DM, can figure something out that will work for everyone in the group.
When someone asks what is your favorite race and favorite class in two separate questions, there is an embedded in the questions. Specifically, that you play with race and class as separate things when playing D&D. That is not how I started playing D&D, so I really can't answer it as two separate questions. Then again, my favorite was presented in AD&D as a separate race with a choice of classes.
When I started, my D&D was a mix of many different systems. I've mentioned Spell- um. er. Flying Grognards in Space before, but another book I treasured was the Dragonlance Hardback. It really belonged to my friend Bill, but he wasn't as taken with it. My group wasn't too fond of the setting because of what we felt like were needless restrictions. Today, I would enjoy Dragonlance, pretty much as written as a setting. Playing it though, would require the rules to be converted to S&W, and the non-weapon proficiencies thing would need to modified, and that whole thing with wizards would need to be worked out as well...
Point is, at the time, we couldn't be bothered with a setting that would tell us that we were doing it wrong because we wanted to learn any spell we wanted and didn't want magic research to go through some committee. I've changed since then, but Dragonlance is the source of my favorite playable race/class.
On page 69, you'll find the Krynn Minotaurs. I loved them. In the setting proper, they could be Fighters, one type of Mage, one type of Priest and a Rogue of little consequence (limit of 8th level). Up to the point of finding the book, I had always played Magic-Users (I changed the word on purpose) or Clerics. I saw that a Cleric-type character was written in the book for Minotaurs, so that is what I wanted to be.
I do not remember his name, but I do remember that I modeled him after Beta Ray Bill. Instead of a twin-bladed axe, he wielded a huge warhammer. He wore chain mail for reasons I never really explained. Per the setting, he was considered a heretic by other minotaurs because he worshiped Kiri-Jolith. For this reason, he left Krynnspace and found a home in a different sphere.
Clerics in my setting were d6 in hit dice. I guess the convention was the same for everyone else because as much as I loved starting with 2d8 Hit Dice (per the Clerics of Good rules in Dragonlance), I started with 1d8 instead, reflecting the minotaur's size and strength. He had no spells at first level, but otherwise progressed as a Cleric.
I believe I only played him once. I enjoyed the concept of him quite a bit, but unfortunately, I remember nothing of his adventures. Oh well. I will check my sources, but this guy may turn out to be someone I created, but never played at all. That happened a lot for me because I was usually the DM.
If you like, I post the Minotaur Cleric class formatted for S&W. Otherwise, thank you for another trip down memory lane in my favorite race/class character.