Which MySQL table to use for read-only, bulk-loaded tables?
This is definitely a loaded question. Why ???


InnoDB caches data and index pages
InnoDB may lock Clustered Indexes during Inserts/Updates
InnoDB is multithreaded and can be tuned for accessing CPUs/Cores
MyISAM only caches index pages
MyISAM must always be read data from disk
MyISAM can have dedicated caches per tables


If you have plenty of RAM and intend to read the same data throughout a business day, some would go with InnoDB. If you are looking for high-speed reads from varying ranges of data, some would go with MyISAM. Even still, there are simply too many mitigating factors to pick one fully over the other such as


VARCHAR field processing
Row Format
Foreign Keys
Index Cardinality
Physical Disk (SSD, SATA, SAN, NAS)
Application Processing Needs


Here are some posts that compare and contrast MyISAM and InnoDB


Sep 20, 2011 : Best of MyISAM and InnoDB
April 12, 2012 : Mysql: Insert performance INNODB vs MYISAM (Not My Post, but good answers are given)
May 02, 2012 : Which mysql storage engine to choose?
May 03, 2012 : Which is faster, InnoDB or MyISAM?
Aug 17, 2012 : When to switch from MyISAM to InnoDB?


Please read these before deciding ...