[Brian]

One thing I've seen fairly commonly from folks new to OmniFocus or GTD is there's a lot of pent-up demand to get everything figured out and be more productive. This leads to a desire to figure everything out all at once, which very quickly becomes overwhelming and discouraging.

You're not alone, in other words. ;-)

The first step I usually recommend is to get used to capturing stuff - it's a manageable task, and the "oh man, I'm not forgetting stuff any more" provides some encouraging feedback. Sounds like you've got that part down.

Next, I usually recommend folks work on getting used to reviewing and picking a manageable number of tasks to work on for the next day/week/whatever. Sounds like you're at that stage.

It's not super-easy at first, partially because of the stage I just mentioned. Previously, you'd idly think about doing something, work on something more important/immediate... and painlessly forget about the other thing you wanted to do if it didn't really matter. Now you've got this app reminding you "oh, I wanted to do this!" So, again - you're not alone in feeling a little overwhelmed. :-)

Thing to remember: it's really and truly okay to defer actions and projects. In fact, it's pretty much necessary - we all aspire to a lot of things. In my experience, we all almost always want to do more stuff than we'll actually be able to get done.

If flagging the 20 items you mentioned wanting to get done is overwhelming, unflag stuff until you feel like you can actually do everything that day. If you get them done early, flag a few more and work on them. If not, re-evaluate the next day and flag a few less next time until you hit the right balance.

Eventually, you realize that you're probably still not getting all 20 things done in one day, but realistically, that was never going to actually happen. In the meantime, you're getting the most important stuff done and getting better at predicting what you can do in a day, which also feels better. It's a win-win. :-)

Hope this helps!