dual boot misplaced boot sector

Because of the curiosity factor involved in seeing how a x64 OS would respond to the digital media apps that I run on my 64bit processor, I decided to install Vista x64 on a spare 40GB PATA drive on my x86 XP SATA setup.
I installed the drive and then ran setup directly from the DVD during startup (I did not boot into XP first.) During setup, in the graphic presentation of the partitions available for installation, I notice that the spare drive (listed in the second column) had some old data on it, so I formatted it and then proceed with the install without incidence.
Upon restart of the machine, after updating some of the drivers, I noticed that I booted directly into Vista without a boot menu showing a choice for a previous windows installation. After another restart to confirm that I had the SATA drive selected as the first boot device in the BIOS, I again went directly into Vista. I then checked the Startup and Recovery settings under the Advanced tab of the System Properties, and noticed that Windows Vista was the only operating system listed. After another restart, I noticed that the installation DVD was still in the drive, prompting me to strike any key for setup, then booting straight into Vista instead of the boot menu or XP. Thinking that the DVD had something to do with the drives being recognized, I ejected it, then restarted and then booted directly to XP. In XP, the Vista installation shows up as my G: drive. In Vista, the XP installation shows up as the D: drive. The drive letter assignments don't bother me. What bothers me is that the bootsector was installed on the wrong drive.
First of all, why would the DVD interrupt the normal boot process like that? Second, how do I get the Vista bootsector installed on the primary boot device, which holds the ntldr/boot.ini files for the XP installation? Can I move the boot folder to that drive? I can't run bootsect.exe in XP from the DVD, because its not a Win32 app. VistaBootPro was no help, either.

Because of the curiosity factor involved in seeing how a x64 OS would respond to the digital media apps that I run on my 64bit processor, I decided to install Vista x64 on a spare 40GB PATA drive on my x86 XP SATA setup.
I installed the drive and then ran setup directly from the DVD during startup (I did not boot into XP first.) During setup, in the graphic presentation of the partitions available for installation, I notice that the spare drive (listed in the second column) had some old data on it, so I formatted it and then proceed with the install without incidence.
Upon restart of the machine, after updating some of the drivers, I noticed that I booted directly into Vista without a boot menu showing a choice for a previous windows installation. After another restart to confirm that I had the SATA drive selected as the first boot device in the BIOS, I again went directly into Vista. I then checked the Startup and Recovery settings under the Advanced tab of the System Properties, and noticed that Windows Vista was the only operating system listed. After another restart, I noticed that the installation DVD was still in the drive, prompting me to strike any key for setup, then booting straight into Vista instead of the boot menu or XP. Thinking that the DVD had something to do with the drives being recognized, I ejected it, then restarted and then booted directly to XP. In XP, the Vista installation shows up as my G: drive. In Vista, the XP installation shows up as the D: drive. The drive letter assignments don't bother me. What bothers me is that the bootsector was installed on the wrong drive.
First of all, why would the DVD interrupt the normal boot process like that? Second, how do I get the Vista bootsector installed on the primary boot device, which holds the ntldr/boot.ini files for the XP installation? Can I move the boot folder to that drive? I can't run bootsect.exe from the DVD, because its not a Win32 app. VistaBootPro was no help, either.

Same Problem except on 32 bit. I installed Vista on a separate partition within the same drive. After initial install, I never got the dualboot option. Vistaboot Pro does not even list the XP OS. The other partitions in the drive are still present and their data intact from what I can tell. Any help would be appreciated, as I may be in over my head.