i've installed vista to D n i 've already installed xp in c:. how can i remove xp,so that at starting also there should not be any os selecting?

If you don't want XP, start over again and reformat C and D, installing Vista on C. Although I have no idea why you'd want to switch...with all the problems Vista has, but that's up to you. Just make sure you have all the drivers for Vista before getting rid of XP. "So won’t you give this man his wings What a shame To have to beg you to see We’re not all the same What a shame" - Shinedown

Why would a guru need to ask such questions? lol I agree with Jennifer. I don't know why you'd wanna dump XP in favor of Vista...most people do it the other way around. An easier solution would be to simply make sure Vista is set as the default OS & decrease the time the OS menu list is displayed. It's probably set to 30 secs...lower it to 1-2 seconds. At least that way you'd still have XP for a backup just in case Vista, ahem, craps out on you.

understand that the vista boots from the xp drive so don't get any ideas of formatting c: or you won't mount vista. This is why its good idea to wipe everything and start with a fresh install.

Try going into Recovery Console and use the diskpart command and delete the partition that has xp on it

deviant, that won't work. Read wanderer's response. "So won’t you give this man his wings What a shame To have to beg you to see We’re not all the same What a shame" - Shinedown