Windows vista boot and Log in screen customization?

Hi i have recently seen a way that i can change my booting and log in screen in windows vista using a program called TuneUp Utilities and i have some questions

1:if i change my boot and log in screen can i restore it back without reinstalling windows and how ?

2:is this program safe to use cause i know that messing with windows system is not something good to do and if it has any side effects( like slowing down computers performance)

3:if i change my boot screen and log in screen and delete the program the settings will still work?



Thanks in advance for the helpWindows vista boot and Log in screen customization?
I've been using that same program. Personally, it seems like the custom boot screens slow my computer down a little bit. But the program overall is safe, and to change the boot screen back to normal all you do is select the default one at the same place you selected your custom one