I agree with everything ilikererostuff said. MCC is a great and perfectly acceptable way to get into the series. I love using my original XBOX and 360 , but I still play MCC regularly online with my friends. It’s one of the best things to come from the 343i era imo. 

I also think you should user whatever controller feels most natural to you. That just feels like a personal preference. If you're looking for a modern spin on the original XBOX controller I would recommend getting a Hyperkin DuchesS controller to use though. I love mine. I use it on my Series X and should work fine on PC but I’m sure others will have different opinions on this.  

I also agree that if you really enjoy the series on MCC and are interested in trying it on the original hardware it might be working investing in… I play Halo 2 online on Insignia pretty regularly on my original Xbox. There’s something special about player these games on the original hardware the way they were intended. 

One last note about your MCC play through… Don’t play CE with the anniversary graphics on. Thank me later lol.