If you were creating a low traffic site to be hosted on a shared ISP (e.g. a cheap www one and not a private one) what DB would you recommend assuming that you could have any of the supported ones?
(I've not used HSQLDB but assuming it's an xml based file)
If you have mysql on hand, use it. hsqldb stores all information in memory while your forum is running, and you may experience problems with your low cost hosting.
Rafael [originally posted on jforum.net by Rafael Steil]