00:24:31.608: Output 'simple_file_output': Number of skipped frames due to encoding lag: 4232 (1474.6%)
00:24:31.608: Output 'simple_file_output': Number of lagged frames due to rendering lag/stalls: 1017 (23.8%)
[...]
00:29:37.821: Output 'simple_file_output': Number of skipped frames due to encoding lag: 1887 (3430.9%)
00:29:37.822: Output 'simple_file_output': Number of lagged frames due to rendering lag/stalls: 609 (31.7%)
I'm reasonably certain that your processor cannot live encode 1080p video, and I'm not sure if it'll manage at all. Change your settings to these:
Output
Output Mode: Simple
Streaming
Video Bitrate: 4000 (assuming you're trying to stream to YouTube)
Recording
Recording Quality: Indistinguishable Quality, Large File Size
Recording Format: flv
Encoder: "Software (x264 low CPU usage preset, increases file size)
Video
Output (Scaled) Resolution: 1280x720
Common FPS Values: 30
Then try to record again.