What has caused my computer to be giving the following messages?
1-8 were noted:
•KHOST caused a general protection fault in module USER.EXE at 0003:00007ae.3.
•YBROWSER caused......in module USER.EXE at 0003:00007af5.
•NAVAPW32.....in module USER.EXE at 0003:00007af5
•LUCOMSERVER...in module USER.EXE at 0003:0007af5
•NMAIN....in module USER.EXE at 0003:00007af5
•YCOMMON...in module USER.EXE at 0003:00007af5
•VBRWICON...in module USER.EXE at 000:300007af5
•EXPLORER .....in module USER.EXE at 0003:00007af5

My pc foze and gave me about 8 error messages after it started closing down

Kontiki

Yahoo Browser

Norton

Is this a recurring problem or did it only happen once?

Also try the Event Viewer:
Start/Run/ eventvwr
Open the System as well as the Application tabs looking for red X errors coinciding with this issue.