An 8 AM PS for a 9 AM EE is not nearly enough time.
You generally want to allow AT LEAST an hour for your character breakfast, probably longer. You may not get seated right away, and it usually takes around an hour for the characters to make the rounds to your table (only once at dinner did it take longer than an hour at Goofy's kitchen); Goofy's kitchen will tell you that you are allowed up to 90 minutes. Add to that, you want to give yourselves time to get to the park, and its strongly recommended that you are at the gates at least 20 minutes before opening so that you are not caught behind a very long line of people at the gate. If I was going to try to have breakfast before going to the park, I'd probably make my PS 2 hours before EE or park opening.
It's been awhile since I've been to the parks during the off-season, but I'm thinking a 10AM opening is probably right for Thursday, but an earlier opening is very possible for Friday and especially Saturday.
Minnie and Friends is open from park opening until 11AM. You won't be able to have breakfast there before DL opens. Goofy's Kitchen has always been my favorite for character meals, perhaps because they seem to have more characters and more variety. The food is probably better than the Minnie and Friends breakfast.
Personally, I prefer to grab a very light breakfast, go to the parks and enjoy the light crowds in the early morning, and then have my character meal a bit later. I like Goofy's at noon when they are open for lunch, or a late seating at one the other places. If it was me, I'd plan a late character breakfast on
Saturday when DL opens early, so that I am eating when DL is starting to get a bit crowded.