If it's another Acer, yes (although technically, no) - probably, at least as far as Windows goes.
Any other manufacturer the answer is likely to be no - it will still wipe the drive, and may have custom software which is incompatible with your machine.
If it's a System Builder disk, you could use that (but if it's the original release version, you'd still be better to download a fresh disk)
i think it was just avast that made my computer crashed because it hasn't happened in a while and my computers faster but now i need an antivirus but do you think a 4gb usb is enough to back up my computer
I would suspect something was interfering with Avast rather than Avast itself causing the problem - which means you may have some serious infection.
Try running TDSSKiller - Anti-rootkit utility TDSSKiller
You should install an AV of some kind - MSE is perfectly good enough .... Microsoft Security Essentials - Free Antivirus for Windows
As far as backup is concerned, it depends on how much data you have - but 4GB is unlikely to be enough if you do anything more than surfing with your computer.
nothing its all still the same i need to back up my pc so i can get a legit copy of win 7 is there any way i can send all my files and applications to another computer because i dont have any money to spend on a external hd
on another note my computer has slowed down a bit almost like its lagging
A clean install with a legitimate copy of windows is always teh best option1 would always be the best option!
ok am about to do the clean install i transferred all my important files to another computer wish me luck
wait which one do i download theres Windows 7 Home Premium x64 SP1 U (media refresh),Windows 7 Home Premium x64 SP1 (old),Windows 7 Home Premium x64 RTM,Windows 7 Home Premium x64 RTM (not bootable),
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