One of my vital tables was being optimzied and MySQL crashed in the middle of it. It then said the table was corrupt. I am running repair but it is taking over an hour, I need this table up ASAP (I will even truncate it if necessary).

Please help me get this solved. The table has about 54 million rows. This is a MyISAM.

Any additional information needed, just ask. Here are the contents of my my.cnf:

[mysqld]
max_connections = 850
max_user_connections = 850
query_cache_size = 128M
skip-external-locking
key_buffer_size = 64M
max_allowed_packet = 8M
table_open_cache = 256
sort_buffer_size = 4M
net_buffer_length = 16K
read_buffer_size = 1M
read_rnd_buffer_size = 1M
myisam_sort_buffer_size = 32M
innodb_file_per_table
tmp_table_size = 100M
max_heap_table_size = 64M
thread_cache_size = 8
wait_timeout=25
interactive_timeout=25
table_cache=600

innodb_buffer_pool_size = 4G
innodb_thread_concurrency = 8
innodb_flush_method = O_DIRECT 

# This setting allows the use of asynchronous I/O in InnoDB.
# The following files track usage of this resource:
# - /proc/sys/fs/aio-max-nr
# - /proc/sys/fs/aio-nr
# Default limit is 65536, of which a single instance of mysql uses 2661 out of the box
innodb_use_native_aio = 1