Visitng Beijing from May 24(9.00 am) to May 31( 12 noon). Please help me in planning my itenary.

Since you plan to stay for so long time, it is suggested you may need to cover most of the famous attractions.
Day 1: Tiananmen Square and Forbidden City and then if you have spare time, you can to to Xidan or Wangfujing area near the square to go shopping.
Day 2: Great Wall and Ming Tombs. In the afternoon, if you have time, you can go to Bird's Nest and Water Cube.
Day3: Temple of Heaven, Summer Palace and Huhai area. In the evening you can go to see the Kongfu Show in the Red Theater.
After that, you have cover most of the attractions in this city and then you can refer to the passage above to find some other attractions that you are interested to.
In my opinion, during the last four days, you can make trip to Xian to see the Terra-Cotta Army, Bell Tower, the City Wall, Big Wild Goose Pagoda, Great Mosque and so on. Four days are enough for you to finish a trip in Xian.
If you want to tour operator to help you, you can contact TravelChinaGuide for help and you can send them emails at travelchinaguide.com|tours. You can just tell them your requirements and they will arrange all the things well before you go to Beijing. You can have a try.

Thanks Demon !.

sorry to butt in - i would suggest making the bird's nest a priority; it is a wonderful piece of architecture and it is a lovely reminder of the last olympic games. also, when i went i found that often some of the museums are really worth a visit - imagine the tate in london, make it a million times better and you have the national art museum (i may have got the name wrong i visited 4 years ago with my boyfriend) . but by all means, if you prefer a more historic city trip, stick to demon's plan.
and by the way, demon, you have an awesome name :)