I don't think so ... it looks like you have no other choice. Since the bootloader shows both operating systems, that means the boot files should already be on the root of the C: partition (drive) that contains Win98. They are boot.ini, bootsect.dos, ntldr, ntdetect.com and ntbootdd.sys. (They are hidden files.) That's why you <i>can</i> boot into one or the other, currently.
The problem, IMHO, is that you need to repair the boot sector, not change the boot.ini file. Generally, when this kind of editing is done, this is for changing a boot order, or removing a reference to a non-existent OS.
You could <i>try</i> changing the "multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /fastdetect", and make it "multi(0)disk(0)rdisk(0)partition(2)\WINDOWS="Microsoft Windows XP Professional" /fastdetect" ... but I don't think it will work.
If you do this, I'd make a backup of the original file, and be prepared to boot into DOS with a startup disk to replace the altered file! (And even that may not work, and you'll end up reinstalling everything!)
Running the repair option is not the same as completely reinstalling the operating system, and should give you much less trouble than you may be imagining. And it may be the safest method, as messing around with the boot.ini can render the system unbootable.
However, afterwards ... you <i>may</i> need to edit the boot.ini file, if WinXP appears twice!
Good luck!
Toejam31
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