"eMachines Recovery Management utilizes up to 10GB of the stated hard disk capacity as dedicated backup space."
Now there was this fellow who installed Windows but did so on the small 10GB partition that eMachines would use for recovery backup space. If you did this and have no OS DVDs then the first step is to find that DVD.
https://secure.tx.acer.com/RCDB/Main.aspx?brand=emachines notes how to order recovery media.
See if you can still make those DVDs at http://support.gateway.com/emachines/notebook/2009/emachines/em/em250/EL1310faq3.shtml
Bob
Emachines Vista OS HD is 150G, C is 10G & D is 140G. C is full (only about 50M empty) and D has 120G available.
C is so full that almost any operation is not allowed. I cannot back up the drive because it requires 400M (using the back up supplied with Vista)
Am willing to lose all the data on D (mainly programs for which the disks still exist.) I do not have the install OS disks so my big fear is loss of C drive contents.

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