I agree with everything Craig has stated.

If I am looking at this thread correctly, one of your challenges is loading into a final target table while that target table is under a query load? If so, the data loading performance guide is a great reference, but ideally you want to have a load time window when minimal activity is happening in the database. However, if you CANNOT avoid this situation, there are ways to mitigate this such as Trace Flag 610 and other stuff in this guide:

http://technet.microsoft.com/en-us/library/dd425070(v=sql.100).aspx