Hi,
I think you mean 20 GB, not 20 MB and only have 2 GB available. This is the likely cause of disk full error messages.
To check
My Computer
Select your C drive
Right Click
Choose & select Properties
Look at the text next to the wording "FILE SYSTEM" in th Windows that comes up. If it does not say FAT32 but says FAT or FAT16 then this is what has happeneed.
The most common cause of this is that when you partitioned and then formated the hard disk you did not say Yes to the question about large disk support when running FDISK.
Solutions are basically 2.
1)
Backup and wipe the hard disk and reboot with a Windows 98 First Edition or Second Edition system bootable floppy disk.
http://www.bootdisk.com if you don't have one. Run the downloaded file to create a bootable floppy disk.
2)
But and install a partition management program. Partition Magic is the program of choice. There are also shareware programs that work in a similar way. Create the rescue disks and backup all data before using PM. Do the various tasks one by one. DOn't set the program to carry out numerous tasks all in one "run"
hth
Ceri