Acer aspire 5600awlmi going slow

Assuming stock LT go to start run and type msconfig and click ok. On the general tab select Diagnostic Startup and click ok, it will ask to reboot and seleck ok. After the reboot see if it is operating normally.

If it is working normally then some application is causing the problem. You can selectivly choose to launch one app at a time till you find the one causing the problem. Most likely is antivirus set too agressivley or spyware. Might consider a tool like spybot to clean the system.