OK. So it seems that the heat buildup is not a function of general operation.
The most effective maintenance is having a backup strategy. Have a look at Dr. Smokes very useful
information page for details.
There are two articles that look at system maintenance from different points of view, yet each provides background information about why it's essential for the smooth operation of the computer.
Macworlds article can be found
here
Dr. Smokes X - Lab article can be found
here
My programs of choice for System Maintenance is
OnyX
Disk Utility: Apple has created this application in part to identify potential file corruption in the system. To rule out any potential directory file problems, run Disk Utility, found in your Utility folder. When the panel appears, select your hard drive. Then go to the "first aid" panel and select on the bottom right "verify disk". If an error condition occurs, you'll have to boot from the Installer DVD, accessing Disk Utility from the Installer Menu. Same step as above, except you would select "repair disk". Continue to rerun until you get a clean pass.
Before undertaking any maintenance I encourage you to familiarize yourself with the above referenced articles. Sometimes, file problems in the operating system can overtax a system creating unnecessary processor activity. Performing maintenance techniques can help reduce these problems.
When you feel complete with this thread, please mark as "solved" so others know your post has been answered.
Good Luck