All right, steppin' up.
I got the log. Two kinds of errors came up while it was frozen.
Freeze time - 7:57:34
00124786 7:57:35 PM [9376] Direct3D9: (ERROR) :BitBlt or StretchBlt failed in Present
00124787 7:57:35 PM [9376]
00124788 7:57:35 PM [9376] Direct3D9: (ERROR) :BitBlt or StretchBlt failed in Present
...
Then:
00124838 7:57:36 PM [9376] Direct3D9: (ERROR) :Failed to lock driver vertex buffer
00124839 7:57:36 PM [9376]
00124840 7:57:36 PM [9376] Direct3D9: (ERROR) :Vertex buffer in stream 0 must be unlocked during drawing
00124841 7:57:36 PM [9376]
00124842 7:57:36 PM [9376] Direct3D9: (ERROR)

rawIndexedPrimitive failed.
00124843 7:57:36 PM [9376]
00124844 7:57:36 PM [9376] Direct3D9: (ERROR) :Vertex buffer in stream 0 must be unlocked during drawing
00124845 7:57:36 PM [9376]
00124846 7:57:36 PM [9376] Direct3D9: (ERROR)

rawIndexedPrimitive failed.
...
Ran ISBoxer to get the admin prompt at 7:57:53.
00208772 7:57:53 PM [4436] Direct3D9: (ERROR) :Lost due to display uniqueness change
00208773 7:57:53 PM [4436]
Left for 10 seconds, then clicked "no" to cancel and free up display:
00208774 7:58:03 PM [8892] Direct3D9: (ERROR) :All user created stateblocks must be freed before ResetEx can succeed. ResetEx Fails.
00208775 7:58:03 PM [4436] Direct3D9: (ERROR) :All user created stateblocks must be freed before ResetEx can succeed. ResetEx Fails.
00208776 7:58:03 PM [9376] Direct3D9: (ERROR) :All user created stateblocks must be freed before ResetEx can succeed. ResetEx Fails.
00208777 7:58:03 PM [8892]
00208778 7:58:03 PM [4436]
00208779 7:58:03 PM [9376]
00208780 7:58:03 PM [8892] Direct3D9: (ERROR) :ResetEx failed and ResetEx/TestCooperativeLevel/Release are the only legal APIs to be called subsequently
00208781 7:58:03 PM [4436] Direct3D9: (ERROR) :ResetEx failed and ResetEx/TestCooperativeLevel/Release are the only legal APIs to be called subsequently
00208782 7:58:03 PM [9376] Direct3D9: (ERROR) :ResetEx failed and ResetEx/TestCooperativeLevel/Release are the only legal APIs to be called subsequently
00208783 7:58:03 PM [8892]
00208784 7:58:03 PM [4436]
00208785 7:58:03 PM [9376]
00208786 7:58:03 PM [1336] Direct3D9: (ERROR) :All user created stateblocks must be freed before ResetEx can succeed. ResetEx Fails.
00208787 7:58:03 PM [1336]
00208788 7:58:03 PM [1336] Direct3D9: (ERROR) :ResetEx failed and ResetEx/TestCooperativeLevel/Release are the only legal APIs to be called subsequently
00208789 7:58:03 PM [1336]
00208790 7:58:03 PM [9376] Direct3D9: (INFO) :Using FF to VS converter
00208791 7:58:03 PM [9376]
00208792 7:58:03 PM [9376] Direct3D9: (INFO) :Using FF to PS converter
00208793 7:58:03 PM [9376]
00208794 7:58:03 PM [1336] Direct3D9: (INFO) :Using FF to VS converter
00208795 7:58:03 PM [1336]
00208796 7:58:03 PM [1336] Direct3D9: (INFO) :Using FF to PS converter
00208797 7:58:03 PM [1336]
00208798 7:58:03 PM [8892] Direct3D9: (INFO) :Using FF to VS converter
00208799 7:58:03 PM [8892]
00208800 7:58:03 PM [8892] Direct3D9: (INFO) :Using FF to PS converter
00208801 7:58:03 PM [8892]
00208802 7:58:03 PM [4436] Direct3D9: (INFO) :Using FF to VS converter
00208803 7:58:03 PM [4436]
00208804 7:58:03 PM [4436] Direct3D9: (INFO) :Using FF to PS converter
00208805 7:58:03 PM [4436]
00208806 7:58:17 PM [1336] Direct3D9: (WARN) :Static index buffer locked more than once per frame. Could have severe performance penalty.
...
and it's now back to the usual warnings.
Attached the full log file.