|Clarify where you're at now?|
Have you edited (at all) the boot.ini as was? If not... copy and post it here so that folks can advise you more clearly as to how it should look - after you've edited it.
Also do you know the folder name of the version now running?
If not then go: Start\run
and (in the run box) type:
and press Enter.
A window will open up listing the current active (booted) Windows folder contents. In the addres bar at the top will be path showing the correct name of the Windows folder you are using; e.g. c:\windows\system - or perhaps c:\winnt\system
Note what is there - hard copy. Yours will likely be windows (but could equally be winnt.... or similar).
The key part is the c:\windows or c:\winnt or similar.
When you find and view the boot.ini - that is the version you want set as default OS to boot; and also is the one "NOT to delete from boot.ini entries.
Setting time to boot to zero ought not to affect time it takes to boot, or actual performance of the version/installation booted...
When you do manage to boot up - look for the other version and see if it is still there on the drive - even though you say you have deleted it... Do this via Explorer or MyComputer.