Windows Control Panel -- Add/Remove Programs
Uninstalling Premiere Elements 8.0/8.0.1 from your computer using Control Panel/Programs does get the program uninstalled, but does not
answer your question which included.
make sure there are no files in my registry.
And, it does not deactivate the program from your computer. Deactivation is not the same as uninstall.
1. Open Premiere Elements 8.0/8.0.1 to its Timeline workspace, then Help Menu/Deactivate. Close out of there.
2. Assuming you are working on Windows 7, 8, or 8.1 64 bit, go next to Control Panel/Programs, find Adobe Premiere Elements 8.0, and uninstall it.
3. Download and install the free ccleaner and do a run through of the computer using its regular cleaner and its registry cleaner parts.
4. After that is complete, use Run, type in regedit, and, in the Registry Editor, go to Edit Menu/Find
In the Find dialog's Find what:, type in Adobe Premiere Elements 8, and do a Find, Delete, Find Next until there are no more Finds for that what you have typed into the Find what field.
Remember if you are dealing with the registry here. If no experience in this area, then keep away from this and settle for deactivation, uninstall, and wherever the ccleaner has to offer, may not be 100%, but close to it.
Please let us know the outcome.