[color:"orange"]I have no idea how to figure out RAM.[/color]
In Windows XP, click on Start | Control Panel, then click on 'switch to classic view' (if necessary) and double click on the System icon. There may be an easier way to get the amount of RAM, and your husband is probably more familiar with the system specs. Since the computer was bought for gaming, if it is not more than a couple years old it should probably have sufficient RAM.
While you are in the System control panel applet, you can click on the 'Hardware' tab, then the 'Device manager' button to check what type of video card you have, listed under 'display adapters'. There may be updated drivers available from the Windows Update site (the service pack and latest critical updates help with BD problems, as well), or you can check directly with the chipset manufacturer, likely
ATI (Radeon) or
NVidia (GeForce).
[color:"orange"]But I have no idea what else should be shut down.[/color]
Anything you do not need running, and many of the things that minimizes to the system tray (by the clock) can be shut down. This includes, email or IM programs, web browsers, wallpaper changers, MS Office quick search indexing 'feature', multimedia players, etc.
The most common effect of running too many background programs would be forcing the game to use the swap file on the hard drive more often (which is much slower than RAM). This would result in occasional slowdowns and pauses, especially with a lot of NPCs, etc on screen, but should not cause a consistent, severe slowdown, I don't think.
The characters in BD do run a little slower than DD at the start of the game, but there shouldn't be an extreme difference.
[color:"orange"]I can't zoom in or out of the maps when in auto-map. I'm in the battlefield area.[/color]
Zooming was not implemented in the BF, since the dungeons are randomly generated.