It seems that some settings are kept even after a reflash. I have a problem with the usb host not working which still exists even after multiple reflashes. I was wondering if it is possible to completely wipe the internal memory (not internal memory card) so I can definitively isolate whether this usb host problem is a hardware or software problem.

Thanks

As far as I know, if you do a reflash (without restoring a back up) the tablet should be back to the factory settings.

Except some settings are kept; for example the password that you used last.

Frankly, that shouldn't be possible (at least, given the information you've provided about the situation). Flashing the device doesn't just wipe settings, or reinstall certain things -- in imprecise terms, it just bulldozes over the entire root device, and gives you a completely clean install. The only cases that I know of where settings could persist would be if you restored a backup, or if you were running a cloned-to-SD install (Flashing only affects the onboard flash, so it wouldn't even touch an OS install on a memory card.)
As for your USB problem, I really don't have any idea. I suppose it's theoretically possible that other components in the device have small amounts of persistent storage for configuration or something, but that's complete speculation, and I would doubt it in this case.
Could you tell us what the nature of the problem is, exactly? That would help.

The mtdblock1 partition holds various config and calibration data, and survives a reflash.

Nice to know. Do you have a link to more information on that?

Not much, but you can extract it with 0xFFFF and try to look around (eg you can see the device lock PIN with strings(1)). Otherwise see this thread and feel free to vote for bug 4874.

The config partition is not affecting your ability to use USB host. The config partition does not contain anything related to USB host. ke-recv and the USB host mode drivers do not read from /dev/mtd1.

That's most likely a ke-recv bug: http://www.gossamer-threads.com/lists/maemo/users/50359

I don't use USB host, myself, but I remember hearing in a bug report somewhere that you need to have a USB gadget module inserted before it'll work (g_ether / g_file_storage are two that are shipped with the N8x0). But other people have used USBControl fine and they haven't been inserting USB gadget modules. I also do not know if this holds true for OS2008 but, like I said, I do not use USB host.

If you read the thread I linked to in the first post I outline the problems I'm having and what I get from dmesg. I'm beginning to think it might be some kind of hardware issue because it persists even after multiple reflashes for which I Did Not restore from backup. However if there are settings for the usb controler in the mtdblock1 partition that are somehow corrupt it's possible that might be what is causing the problem. Otherwise I'll just return my tablet to Nokia though I'm not sure how willing they will be to replace it if it has a problem with a feature that they don't really advertise.

I'll try the suggestion in the link and see if it works, though I'm not experienced with compiling from source, are there any options I would need to set or do I just do configure, make, make install ?