information that should help you find out what is causing the crash.

091130 11:16:11 - mysqld got exception 0xc0000005 ;
This could be because you hit a bug. It is also possible that this binary
or one of the libraries it was linked against is corrupt, improperly built,
or misconfigured. This error can also be caused by malfunctioning hardware.
We will try our best to scrape up some info that will hopefully help diagnose
the problem, but since we have already crashed, something is definitely wrong
and this may fail.

key_buffer_size=26214400
read_buffer_size=65536
max_used_connections=0
max_threads=100
threads_connected=0
It is possible that mysqld could use up to
key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 58231 K
bytes of memory
Hope that's ok; if not, decrease some variables in the equation.

thd: 0x0
Attempting backtrace. You can use the following information to find out
where mysqld died. If you see no messages after this, something went
terribly wrong...
006B8853    mysqld.exe!srv_parse_data_file_paths_and_sizes()[srv0start.c:211]
006A7E18    mysqld.exe!innobase_init()[ha_innodb.cc:1536]
00442748    mysqld.exe!ha_initialize_handlerton()[handler.cc:434]
00561253    mysqld.exe!plugin_initialize()[sql_plugin.cc:1002]
00565AE5    mysqld.exe!plugin_init()[sql_plugin.cc:1209]
004CE1B4    mysqld.exe!init_server_components()[mysqld.cc:3831]
004CE8C6    mysqld.exe!win_main()[mysqld.cc:4267]
004CECDB    mysqld.exe!mysql_service()[mysqld.cc:4439]
00724593    mysqld.exe!_callthreadstart()[thread.c:293]
0072462C    mysqld.exe!_threadstart()[thread.c:275]
7C82482F    kernel32.dll!GetModuleHandleA()
The manual page at http://dev.mysql.com/doc/mysql/en/crashing.html contains
information that should help you find out what is causing the crash.
问题补充：
我把 my.ini 文件里面的table_cache=256 这句暂时注释掉。问题解决了。