The changes to the prequels are very minor, nothing comparable to the special edition debacle with the original trilogy. That being said, D+ will give you the highest quality. I’m partial to the 4K Blu Rays, personally, as I like physical media.
Disney+ is better quality than the 4K discs? Is that for all the films, or just the Prequels?
OP was asking about Disney+ compared to the original DVDs. But to your question, 4K Blu Ray will always provide the best quality without compression.