15:09:01.376: Windows Version: 10.0 Build 17134 (revision: 523; 64-bit)
Windows is out of date and Game Mode is on by default and cannot be switched off. This mode is designed to allow a single app (a game) near-exclusive access to the GPU. This prevents OBS from working properly, which shows up in the log like this:
15:22:59.981: Output 'adv_file_output': Number of lagged frames due to rendering lag/stalls: 86 (2.5%)
15:25:37.502: Output 'adv_file_output': Number of lagged frames due to rendering lag/stalls: 2395 (36.4%)
15:27:18.930: Output 'adv_file_output': Number of lagged frames due to rendering lag/stalls: 3004 (52.9%)
You should run the October 2018 update and turn off Game Mode in PC settings. Instructions are at the link in the signature below.
You also have encoding lag, which is this:
15:22:59.992: Video stopped, number of skipped frames due to encoding lag: 2185/3161 (69.1%)
15:27:24.283: Video stopped, number of skipped frames due to encoding lag: 3076/3183 (96.6%)
You're using the x264 encoder for recording on an i3. You're also recording at a very low bitrate (2500) and at 1080p60, which is challenging. In any case, for local recording you'd be better off with CRF rate control and a quality setting between 15 and 23 rather than a constant bitrate-- CBR is mostly intended for streaming, not recording.
You are completely overloading a machine of very modest capabilities. I would suggest running the Auto-Configuration Wizard from the Tools menu to develop some more reasonable settings, but in general:
Use the QSV (QuickSync) encoder if your machine supports it.
Use rate control based on quality rather than bitrate when recording (lower numbers mean higher quality and larger files)
Record at 1280x720 at 30fps instead of 1920x1080 at 60fps.
Don't record in MP4. Use MKV or FLV, and after recording, remux into mp4 with the Remux option under the File menu. MP4 files that are interrupted by OBS crash, system crash, or insufficient disk space errors will be unrecoverable. MKV files after such interruptions can be used.
15:20:06.650: YUV mode: 709/Full
Undo that change, you'll be negatively affecting the appearance of your video when played back in most web browsers.