OS : windows 7 32 bit
CPU : interl(R) Xeon(R) CPU E5462 @ 2.80GHz 2.79GHz
Memory : 4Gb
VGM : ATI Radeon HD 2600 XT 256 MB
when I resize image, I press shift & alt button.
and all image were outline stroked.
Are you working with the Scale Strokes and Effects box checked in the Preferences (or Scale dialog) and is Align to Pixel Grid checked in the Transform panel and panel flyout?
edit -> preferences -> general
-> uncheck the Scale Storkes & Effects
windows -> transform -> (show options)
-> uncheck the Align to Pixel Grid