As A normal user of Vista i dont like vista User Account Control (UVC)
User Account Control can help prevent unauthorized changes to your computer.
how to completely stop appearing just do following step
1) click start button
2) go to control panel
3) User accounts program
4) click on Turn User Account Control on or off link
5) remove tick from check box. press ok
6) after restart you never face UAC
If your pc give the below error than do the below step to resolve error
NTLDR is Missing
Press any key to restart
Solution :-
1. Change your pc boot Priority and make first boot cd rom/dvd
2.than restart from cd and wait till it ask you for press r for Recovery
3. press r
4. choose which windows if you have more than one os install in your pc write the number and press enter key
5. provide your pc's administrator password and run below command to reslove the problem
copy e:\i386\ntldr c:\
copy e:\i386\ntdetect.com
here, e:\ is the cd rom drive
if it ask for overwrite than press "y"
than,
write exit press enter
than root from your hard disk
now window will start work
If you want more details below is the link
http://support.microsoft.com/kb/318728
