1) No, you don't need research experience. Lots of people aren't interested in research and get accepted without any. If you are aiming at a Top 20 MD school, though, you should get some research experience. Those schools are very research oriented and expect to see some research.
2) A little confused by the years mentioned in your post. Do you mean applying this year to start school in 2012? I don't think you are in a good position to apply to start in 2012. For one thing, you say you will "study all summer" for the MCAT. So you are planning on taking in August or September 2011? If so, your apps won't be complete at schools until your score is sent in August or October and your apps will be "late," putting you at a great disadvantage. This is such a competitive process early is really, really key. You want to be one of the first applicants to submit in June and finish secondaries ASAP when you start receiving them. Also, with absolutely no clinical experience right now you would only have a few months of experience to show on this year's app. IMHO, adcoms are just going to think this doesn't show enough long term commitment. I think you are much better off waiting another year, making sure your MCAT is solid and getting some shadowing and volunteer work under your belt and applying to start in 2013. If this is what you meant, yes, I think with some solid clinical exposure hours over the next year you could be competitive. Of course, this is assuming good grades and a solid MCAT score.