I run 7.5 on mine and it runs really well, I know a lot of people would say to use 7.1 but 7.5 seems to run as fast as you would expect anything to run on a 8mhz computer from '86. I will admit i have never run 7.1 on my plus, only ever 6.0.8 or 7.5, but i wouldn't think you gain much speed from using 7.1 over 7.5.

As for the word processor, i think word works very nicely on the plus, but i don't see much between word processors on it.