Running Windows 8.1 on Lenovo G505s with 6 GB ram and 2.4 GHz 4-core CPU.

For the past week or so, I noticed that my laptop has been running slightly slower, has gaps or pauses where no user input is accepted, and my battery has not been lasting as long. Today, I looked at my task manager to kill a non-responsive app, and noticed 80% of my memory was in use, and 70% of my CPU was used up. Turns out both the top spots are taken by "Service Host: Local Service" which is using 15.9% CPU and 359.3 MB RAM. I use this laptop every day for school where for about an hour, I don't have access to a charger, so I need to have as many high profile tasks killed as I can safely do so. The processes running inside Local Service are:
  • DHCP Client
  • HomeGroup Provider
  • Security Center
  • TCP/IP NetBIOS Helper
  • Windows Audio
  • Windows Connection Manager
  • Windows Event Log

The high CPU usage gets worse when I don't have a separate mouse plugged in because my Touchpad drivers take up anywhere from 13-50% CPU, which has been slowing me to a crawl. Is there anything I can do to keep my computer running, but with more available resources short of going out an buying more? I have to be at school with this machine in 2 hours.