With Windows ME, you have to boot-up with a Windows ME startup disk (floppy disk) to get to a DOS screen. If you didn't make one while Windows was working okay, you can download one from here on a working PC (doesn't matter what version of Windows the working PC is using).http://www.bootdisk.com
Click on the green BOOTDISKS link at the top, then click on the 'Windows ME OEM' download link. When the file has downloaded, shove a blank, formatted floppy in and run the file to create the boot disk. Then shove it in your ME system and boot from it.