OK... if your camera has issues... may be driver problem... as far as I know, there are NO drivers for windows 7, instead, windows 7 install a driver for it, but the bad point is that the driver is deficient, so your best chance is to get the original OEM drivers that came with your PC.
If you don't have them, I have a set of OEM drivers for my Aspire 4535 (that I backed up before doing a clean install of Windows 7 Pro without all the bloatware) that uses the same camera as your Aspire One... the model is Chicony. This driver includes the utility to see your webcam without the need of the messenger or other stuff.
If you need it you can download from here:
Chicony Camera utility Crystal Eye.rar
Execute ONLY the "setup.exe" file, nothing more, the rest are scripts for the Acer recovery system auto install feature...
I hope this can help you.
Anyway... you can try recovering the OEM software that came with your Aspire One... why don't you try Recuva, this utility can help you recover deleted files (even from formatting the HDD) do a scan in your C: drive, the important stuff may be located in a folder called Preload, and inside, a folder called OEM...
See ya!!