I would suggest you follow a Lydiard maxim of "mileage first, then intensity".
Stick to zone 1 HR initially. This should allow you to build your mileage rather quickly, and keep the stress to a minimum. Be careful though... to avoid overuse injuries by building too quickly.
Don't get too locked into an arbitrary goal for volume. Going from 2 hours to 8-9 hours is a HUGE jump. You may be able to handle that, but don't be surprised if your sweet spot for this training cycle is lower. (I've had numerous setbacks by forcing things in this department... remember - "mind over matter" doesn't work too well with overuse injuries.)
Anyway, build in zone 1, until you hit your volume goal, or until you find your personal limit. Then do a couple of weeks (at least 2) at this level.
Also, I would hold off on the speed work until you've built a nice base. Adding in intensity will only detract from your volume initially. There is a time and place for speed, and that's mostly a bit later in my opinion.
Once you're sure you can handle that volume, start replacing some zone 1 miles with zone 2.
You'll find, like Lydiard promised, that you can achieve your goal much faster progressing this way (2-step process) than if you try to run your miles faster (zone 2) right away.
A few weeks in, I almost guarantee you'll be tempted to move into zone 2 as you start feeling good. Challenge yourself to go further, rather than faster, in those early months.