When you integrate SSRS with SharePoint, by default the Report Builder is 1.0. You can install the Report Builder 2.0 and configure SharePoint to use it instead. But you are going to run into issues if your SharePoint environment is 64-bit.
Reporting Services Add-in for SharePoint products and technologies is not installed. It must be installed before you can install the SQL Server 2008 Report Builder 2.0 for SharePoint.
A way around this is to copy the Report Builder files from the SQL Server installation over to the SharePoint server 12 hive. You’ll find the ReportBuilder files located here: SQLSERVERINSTALLLOCATION\Reporting Services\ReportServer\ReportBuilder
Don’t copy the whole folder, just the contents. You’ll need to copy them to the following directory in the 12 Hive. C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\ISAPI\ReportBuilder.
Note: the files are about 335 MB, and make sure you take a backup of the original files just in case.
Now Report Builder 2.0 will work in your 64-bit SharePoint environment.