Exploring the website for three hours, you probably already found this:
best-gmat-books-77703.htmlIf not, review it and perhaps ask a few follow-up questions there. For verbal, you have the right idea: Powerscore CR and
MGMAT SC are the most reliable. Only buy an RC guide if you notice a problem with that question type. For quant, most find the Manhattan math series quite effective. And yes, the OG is a must.
For visual learners, reinforce concepts learned with high-quality questions. The first choices should include the OG, GMATClub forums, GMATPrep, as well as the online CAT's and question banks from Manhattan. However, make sure that you conceptually understand these concepts. You need that skill for the test.
Two hours a day might not be enough. For the weekdays, do what you can. But for the weekend, you need to invest a great deal of time for a good score.
How to define an acceptable score depends on the school. The application process, of course, involves a lot more than the GMAT (as you probably already know). Don't focus too much on that now, though. Just put all your efforts into constructing a solid study plan and following through.