Not quite sure what your saying here, You want to wipe the drive but not reformat it is that it? Why don't you want to reformat it?
If your trying to save your OS then use an Image program to back everything up then just start deleting or installing programs till you get down to the OS. If you want to lose everything reformat is the quickest way.
Compaq Presario CQ5305K-m Intel® Pentium® Dual Core E5300 (2.6 GHz), Windows® 7 Home Premium 64 bit, 2048 MB , Hard drive: 320 Gb, with 18.5 Widescreen
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