See this site:
http://linux-ntfs.sourceforge.net
Linux has trouble writing to NTFS partitions. Even if you get it to work, there's a small chance data might be corrupted. You can't really change the file system type Windows runs on unless you're using Windows 95/98/ME, which use FAT32 instead of NTFS. Windows 2000/NT and Windows XP are stuck with NTFS until the next version (Longhorn) releases OFS aka "Windows" FS.
About the "755", imagine that 4 = read, 2 = write, 1 = execute.
So the first digit means that the owner of the file and root can read, write and execute (4 + 2 + 1 = 7)
The second digit means users in the same group as the creator can read and execute but not write (4 + 1 = 5)
The third digit means that all other users can read and execute but not write (4 + 1 = 5)
733 means that the creator and root can do everything, but everyone else can only write and execute, not read. (2 + 1 = 3)