FAT32 and NTFS
no. formatting a hard drive means completely removing all files, including windows...
If you are going to format the drive first then there are two possibilities: 1. You have all system and personal files on one drive. In this case you would lose all your files. 2. You have system files and personal files on different drives. In this case you would only lose the files on the drives that you format. As long as you don't format the drive with your personal files on it you won't lose them.
If you format the partition where windows files are located, you will loose all data on the partition.
No, Windows Media Center does not convert AVI files to DVD format. However, it is capable of playing most AVI files.
The hard drive D: is usually the recovery drive for most Windows operating systems. It's best to stay away from that drive if it is.
Format it or delete it.
There's no such thing as Windows XP format or Windows Vista format. You should check however if your external hard drive uses an NTFS or FAT32 partition table. You can see that by right-clicking the drive (C, D, E, ..) and clicking properties. If it uses NTFS it will be no problem for Vista. If it's FAT32, then google for a way to convert it to NTFS. No big deal.
Windows
.JPG files are a well established standard format that can be used on most computer systems, including Windows and Macs, without any problems.
No.
Your songs on iTunes are sound files. If you downloaded them from the iTunes store, they are .m4a files. If you downloaded them from elsewhere, they may be in a different format, but they are still sound files. To locate the files on your hard drive, simply right click on a song on iTunes and click "Show in Windows Explorer" (at least on Windows).
no where it just deletes all the files there