Live crashes when working with two tracks/

[phillytomcat]

Hi, I was loading two tracks in Live for chopping up in session view.
I loaded two saved edits. I realized that they were the same and sounded horrible.
I tried to stop one of the clips and my gui froze. However, music kept playing.
These were youtube ripps from our choir session.
Is the user error or live.
Specs of computer:
Toshiba Satellite C655.
2.3 ghz Intel Pentium
4gig Ram.
Windows 7 64. ty