To begin, there is an old saying
"if it's not broken, don't fix it" that said, another point I think the others are getting at is that there are two boot loading systems, I have been struggling with moving my XP/Win7 dual boot to another HDD, and have picked up bits and pieces as I struggle through this quagmire (lol) XP uses
ntldr and
ntdetect.com and the text editable
boot.ini file. Win7 uses
bootmgr and points to
winload.exe which will be located on the target partition anyhow.
I may be wrong but it sounds like what you are asking is to emulate what everyone is talking about creating the 100MB boot partition setup. Which I am not familiar with myself since I did a traditional XP install and then later added on Win7 on the second partition.
Thing is if XP is loaded first and Win7 after on the 2nd partition. Bootmgr doesn't actually remove the original XP boot system but 'deactivates' ntldr by rewriting the MBR to look for bootmgr first instead and then 'subsumes' the XP ntldr under its own bootmgr, as you must notice when you boot. The Win7 bootmgr runs, and if you select XP, you can see that it has actually then just initiated the ntldr / boot.ini setup. i.e. you can now see the previous boot.ini file that was loaded by the ntldr system This is two separate boot loading systems.
So I agree there's loads that could go wrong if you play around with this too much, on the other hand if you enjoy the learning process which I normally do when I am not in a hurry to get a system up and running, and you don't mind taking the risk of experimenting, there is always the long term advantage of developing a deeper insight that will come in handy on future installs... it's all trade offs... but that is what I am going through right now, call me jaded but this isn't fun anymore, (especially when it feels like MS is just making things purposely difficult to maintain the value of their quasi useless MCSE certification money pit, but that's another story...)
Technically assuming you have a setup as described above which is how mine is, and you really wanted to do this (but I agree with Greg I don't see it being practical imo) if you know how to read the boot.ini file you could tell it to go to the next partition, and then move your whole XP partition image there, but then you would have an issue because XP which was originally a C: drive OS for example, would now be on D: and that would raise all kind of havoc. Same issue for Win7. And that, I currently don't have any answers for although I think there are some tools inside the OS for transferring relevant info to another drive letter, etc but I have never futzed with the internal MS file utilities, preferring instead to just backup the entire partition (although maybe I should start playing with it, the way things are going... anyhow...
On that note I have also found a couple of 'bugs' in the EasyBCD editor that are confounding my efforts, like it won't copy backup BCD images to designated folder paths, and it doesn't want to rewrite the MBR for XP as it does for Win7, so I am now double checking everything I am doing. Thus the one motto that has stead me well through the ages of (MS) is "if it's not broken, don't fix it"
For more context on this understanding which may help you decide if this is "really" what you want to do, I would check out this page
Windows XP - EasyBCD - NeoSmart Technologies Wiki It will give you more insight on this ntldr vs bootmgr issue. I also read someone installing OS's on primary drives bootable from each drive, and then using a Master Boot Loader software Like Grub that would choose between OSs on start up. But that sounds like a ground up rebuild...
I may consider something like that as well in the future, as an ultimate solution. But I won't attempt it as just an "add on" adjustment to my original setup. The issue I have there is apparently it will boot the chosen OS as C: and that will realign all the other partition letter assignments, in particular it will bugger my personal data location on E: and if I chose Win7 it will load that as C also. ie My traditional XP on C and Win7 on D and personal data on E goes bye bye. Multiple primary partition behaviour changes all that.
Multiple primary partitions I have noticed operate very much using the old DOS rules of having 2 hard drives each with primary partitions and extended logical drives, It will make the partition of whichever hard drive has an active primary C: then assign D,E,F to the logicals of that drive AND THEN assign the next letter to the NEXT primary partition and assign the additional letters following that...
ie. it treats each primary like DOS would if you had two physical hard drives both with a primary partition and logical partitions on each. Now if you have Two HDDS with multiple primaries it's even messier (imo) but that's another story... (haven't bothered to go that far yet)
So far I have forced letter assignments on my single disk with 3 primaries in Diskpart to contain that but I don't know how solid that is, as I have seen in the Win7 recovery CD that it reverts back to the old DOS algorithm. And I think I saw my second primary as K: (I have 10 partitions, with 3 primaries. So for example it assigns C: to first primary, assigns the following letters to the remaining 7 logicals D-J, then goes back and assigns the 2nd primary partition as K: What is old is new again! (lol) just my two cents...
