clean install vs upgrade

Hello, i see different explanation and i understand not. 1)-what is clean install ? does that mean that vista shall only stay ? i read that i shall have a folder "windows.old" or other, may i delete those folder ? I will only vista. In this case i have a program and maps from my gps, shall i keep this or must i do a restore from the program and maps ? 2)-what is upgrade xp ? does this mean that i have xp and vista ? in which case 1)-, 2)- or 1) & 2) can i come back to xp ? and how ?
definitively i will only vista on my pc and i will hold my gps program and maps. How must i do ? witch solution clean or update ? thanks to you

A clean install means that any previous version of Windows is replaced without keeping your files in their original places. An upgrade means that files are left in their original places. If you are not experienced with installing operating systems and working with device drivers you should not use Vista now and should wait for the final release early next year. This build of Vista is not for general consumer use.
"benoit" wrote in message

Hello, i see different explanation and i understand not. 1)-what is clean install ? does that mean that vista shall only stay ? i read that i shall have a folder "windows.old" or other, may i delete those folder ? I will only vista. In this case i have a program and maps from my gps, shall i keep this or must i do a restore from the program and maps ? 2)-what is upgrade xp ? does this mean that i have xp and vista ? in which case 1)-, 2)- or 1) & 2) can i come back to xp ? and how ?
definitively i will only vista on my pc and i will hold my gps program and maps. How must i do ? witch solution clean or update ? thanks to you