Why did you delete your post?
Anyhow, according to Acer your network device is Broadcom 4401. There are Vista drivers available, and these may or may not work in Windows 7. Note that you might have to install them in Compatibility Mode. Broadcom.com - Ethernet NIC 4401 Driver Downloads 32-bit: Broadcom.com - Broadcom License Agreement 64-bit: Broadcom.com - Broadcom License Agreement
Note that the above are listed on the support page as being Vista drivers, however by the file names they look to be XP ones. Even so, try them, and if they are XP ones see if you can get them to install using Compatibility Mode. Compatibility Mode
Note that as your laptop is an old model, there is no guarantee with any of this. Best of luck.