Lagging or hanging can be a hardware related concern as well. Please do try these troubleshooting steps that may help.
- First is to test it our in BIOS, do observe if the laptop will still freeze or not.
- If it will not that means you're motherboard is okay and CPU but if it will that could mean either the motherboard is faulty or it's overheating.
- If the laptop is working properly in BIOS proceed with loading it in BIOS.
- While the laptop is booting up, repeatedly press on F8 until it loads Advanced Boot Options, select Safe Mode then press Enter.
- Once the laptop is in Safe Mode, do observe if it will still lag.
- If the laptop will still freeze in Safe Mode that could mean that the HDD is bad.
- Do a clean install of Windows then observe it again.
- If the same problem will persist, consider replacing the HDD.