I want to reset the user account after log-off/reboot

After I will format the computer, install all programs and made all setting I would like to save this configuration and made it ‘locked’. So everything I will do will be temporary and it will be reset after I log-off or reboot. So that nothing is (can’t be) saved, no program (script) installed. So that I cannot get a virus or anyother malware. All my files will be saved on another drive (eg. partition).

Is this possible to do in Windows 7; no server, no domain, no additional sofware required?
Or any other better solution?

Thank you for assistance.