I found Windows ME to be rather fragile, and it would fall over at the slightest push.
A quick solution is the next time this happens, re-scan the disk from within Windows, (ie after you have cancelled the full scan), but just performing a quick scan. That completes the checking process for the flag that failed to be reset when ME failed to shutdown properly, and the next time you start up the computer the scandisk should not appear.
However, that will ony work until the next time a shutdown fails. What you could try is a complete scan then a defrag in Safe Mode, (it is quicker that way as no other processes are loaded). Carry out the scan first, then the defrag to try and keep the machine in a tidy a state as possible.
You may want to run Diskcleanup as well before running scandisk, (Start > Programs > Accessories > System Tools > DiskCleanup.
whenever there is a improper shutdown of my pc, i have to scan disk. but most of the times, my scandisk never progresses for more den 3 blue bars. so, i had no choice but to cancel the scandisk.
and i also face a problem with restarting my computer. I can shut down my computer properly but if i choose restart, it hangs on a black screen. and i have to reset the whole pc again.