I suppose your Acer is running Vista otherwise Win7 should have handled all those major drivers.
If all fails then inevitably you'll have to restore it back to factory settings, instruction below quoted from Acer site:
Restore and recovery
The restore and recovery features allow you to restore or recover the system from a factory default image, from a user created image, or from previously created CD and DVD backups. You can also reinstall applications and drivers for your Acer system.
1 Press + or select Acer eRecovery Management from the Empowering Technology toolbar to start Acer eRecovery Management.
2 Switch to the restore and recovery page by selecting the Restore button.
3 Select the backup point you would like to restore from. You can also choose to recover the system from a factory default image, recover from a previously created CD/DVD or reinstall applications and drivers.
4 Follow the instructions on screen to complete the process.