To lock table or not to lock

I asked this on Thelist and the MySql lists and didn't get any usable answers, perhaps someone here can help. I am having some problems with my mysql server crashing. I THINK I have narrowed it down to multiple records being written a the same time. Atleast today that's the case. There are several entries in the db around the same time the server crashed, however, there are other entries earlier in the day at the same time and the server didn't crash. Who knows..... Anyone? Why wouldn't I want to lock the table? Thanks for the help. CDitty