The main difference between the Yeti and Yeti Pro is that the Yeti Pro has both USB and XLR inputs. The Yeti Pro would be more versatile, but the XLR input would be useless if you didn't buy an audio interface. Honestly, I'd pick the one that suits you the best. Both of them sound nearly the same without post-production of the audio, and with post-production, the difference becomes almost indistinguishable.
If you're on a tight budget, I'd go with the Yeti.
If you want some more options outside of a USB microphone, without having to buy an XLR microphone, I'd buy the Pro.
As for the accessories, I would recommend getting a pop filter and shock mount. The windscreen is only useful if you breathe heavily, or if there's a consistent breeze of wind in your room. However, all 3 of these are very cheap to obtain, so it might be worth getting all 3 of them.
Depending on your situation, I would recommend getting either a microphone scissor stand (These things):
Or getting your standard microphone boom stand. If you use a camera, I'd highly recommend the boom stand, as it has more maneuverability. However, if you have a normal setup, near a desk, get the microphone scissor stand.