When you try to install sharepoint 2010 RTM version, you might get some error messages while installing the SharePoint and once you have all updates for your windows 2008 SP2 / R2 and SQL 2008 SP1.
Here is some points to put into your consideration:
1) Before start installing SP 2010 by double click on setup.exe try to check your pre-requisites software required on your system.
2) You can install all your pre-requisites from this url:
3) After you download and install all required and start running SP 2010 RTM setup you might get this error message:
Error : This product requires Microsoft filter pack 2.0 sharepoint 2010 RTM
Even if you installed the Filter pack 2.0, you will get this error, to fix it you will find a folder in sharepoint 2010 folder called "PrerequisiteinstallerFiles" -> Filer Pack : inside this folder you will find filter pack 2.0 exe file.
4) Then run the following tool PrerequisiteInstaller.exe in the sharepoint 2010 installation folder and make sure you passed all required software to start installing SP 2010 RTM.
5) Run sharepoint setup file setup.exe.
You will have a successful setup and then you will run Sharepoint configuration wizard to complete the installation.
Hope this helps.