Hi,
Yes you should be able to boot from the Windows 10 on the DVD... Providing it was created properly..
How did you put the ISO on the DVD ?
I just tried making a Repair CD on my Windows 10 build 19041 (2004) machine, and it booted properly..
I think your Windows 7 Repair CD should boot normally even though you are running Windows 10..
All of it's features may not work properly, but it should at least finish booting.
I will check my machine nd let you know what happens..