The Base System Devices are most likely your 5-in-one card reader. You need to install the drivers
for those from the Acer website. Windows 7 does not have those drivers.
Go here: Acer Europe - Service & Support, Drivers & Utilities, Downloads, Notebook, Aspire 5720
Download the "Cardreader" driver
for Vista/XP and install it. Chances are it will install fine as is. If not, you can run the downloaded installation file in "Compatibility Mode" for Windows Vista as Tews suggested.
Then Download and install the drivers for you webcam ("Camera" on the driver list). You need to know which camera your laptop has, as there are 3 brands listed.
Download and install any other drivers for your laptop from the website until all the devices are working and all the yellow triangles are gone.
Hope that helps.