The computer shop yanked your crank.. you may not have an AGP video card slot on the computer, but you can get a 3D graphics accelerated video card to fit a standard PCI slot, for about $50 but the onboard video should be 3D Accelerated, ATI Radeon is what ACER uses for that, if you have an ATI Radeon sticker on the case, you have a driver issue with Vista ( common problem ).. go to control panal, and then go to system and then device manager, check to see if there is issues with the graphics card, a yellow ! will be next to any drivers/ devices with issues . I happen to know that ACER uses generic
parts, so there generally the most upgradable of the off the shelf computers, and all off the shelf computers still have a few PCI slots for upgradability.

If you do have driver issues, call Acer, there probably going to be no help at first ( the help desk is what this is, and they try to resolve your problem w/o getting a tech which never works), but create a ticket so they have record of your issue, ask for a ticket number, do what they say, when it doesn't work call them back, give them your ticket number and ask to have the ticket escalated, and get a tech to give you the correct answer. I have an ACER Aspire 3100 laptop w/ Vista basic, I have had 3 driver issues, because vista changes drivers, and lots of times, makes them not work.