I want to install but R3 but are there any hotfixes I need to install before doing so?

Contributed By: Cliff Hobbs [MVP ConfigMgr]
Yes as detailed in KB article 977384 "Description of the prerequisite hotfix for System Center Configuration Manager 2007 R3" you need to install the prerequisite hotfix detailed in this article on any computers in your environment running ConfigMgr 2007 SP2 that are:

• Primary and secondary site servers
• Remote administrator console servers
• Remote provider servers
• Client computers

You can request the hotfix (which is ~5.6 MB), via the KB which you can view at:

http://support.microsoft.com/default.aspx?scid=kb;en-us;977384