My ibdata1 is 395mb, is that what you're curious about? Right now with both 4 and 5 on the system, it's hard to know which admin tools to run to look at things and I don't want to run anything that might mess things up. Things are tenuous enough as it is

When I installed 5, in fact, it gave me an error about not accessing the root account without a password - when I did have a password on 4 and had specified a password for 5 during the install process. So I'm not quite sure what is going on yet.
Should I just run the "migrate" utility that came with MySQL 5, to bring the tables in from 4 to 5? Or should I do a database export in UBB, then somehow connect UBB to the 5 database and do a re-import? Can you even do that?
OK I did risk running the SQL admin, the data len is 351mb and the index len is 119mb.
The hosting guys say said:
"What seems to be occurring with your system prior the hanging/reboot, the FTP, HTTP, and SMTP processes exit unexpectedly. These events usually occur about 50 times in sucession before the system finally crashes. Associated with these process errors are errors having to do with the ubbthread.php script which is the primary piece of code that runs your message forum."
When I look at my error logs, I see lots of timeout errors even though my system shows it's only using 30% of its processor power and 50% of its memory. The system isn't "busy" and it's not doing anything else really. It's a dedicated machine.
The event log is full of errors like this: "The World Wide Web Publishing Service service terminated unexpectedly. It has done this 11 time(s). The following corrective action will be taken in 0 milliseconds: No action. "
SMTP, FTP and IIS Admin are doing the same crashing.