Here are steps you can take to inspect the cause for slow and freezing computer performance:

1. Check your hard drive space for available disk space
2. Check your installed applications for high resource use
3. Check your running processes for use of unwanted programs
4. Check your system event logs for errors
5. Clean your disk of temporary files and applications
6. Update your system driver, operating system, and other installed programs
7. Check for malware and viruses