Windows 10 revert difficulties

I have a Dell Studio 1550 that had the forced Windows 10 "upgrade". I followed the instructions to revert (from recovery) as it had been less than a month. But then I was given Boot Manager:
Windows failed to start. A recent hardware of software change might be the cause. To fix the problem:

1.Insert your Windows installation disc and restart the computer.
2.Choose your language settings, and then click "Next".
3.Click "Repair your computer."

If you do not have this disc, contact your system administrator or computer manufacturer for assistance.

Status: 0xc000000f

Info: The boot selection failed because a required device is inaccessible.

I went to my other comp whish has windows 7 to create the disc - but I apparently have Windows 7 64 but on the dell not the 32 bit that was downloaded and am at a standstill.

I just wanted to play Minesweeper dammit! Help?