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Is the 'Dell Touchpad' tab not showing in your Control Panel --> Mouse properties?
If not... go the the 'Drivers & Downloads' page on the Dell website (linked to at the bottom of this page - under 'Support'), and download/install the touchpad drivers.
Once the drivers are installed, open Control Panel --> Mouse --> Dell Touchpad.
Click on the large screen with an arrow, which will open the touchpad configuration window.
Click on 'Device Select', and right at the bottom is a box which you can tick to 'Disable Touchpad/Pointing Stick when a USB mouse is connected.
As soon as you tick that option, a message will pop up in the taskbar, confirming your selection.
You can make doubly sure however, by also choosing 'Disable' under the Touchpad' heading in the same window.
Be sure to click 'Apply' once you've made your selections.
From experience, I've found that: “Beauty is in the eye of the beer-holder”!!
Smoke Grey Magnesium Alloy Chassis - with White LED Backlights
17" UltraSharp WUXGA Widescreen TFT (1920 x 1200) with TrueLife
Intel Core 2 Duo Processor T9300 @ 2.50GHz (800 MHz FSB, 4MB L2 cache)
4GB (2x 2GB) Patriot Signature PC2-5400 @ 667MHz
DUAL 512MB Nvidia 8800M GTX cards in SLi + 128MB Ageia PhysX
640GB SATA II (2x 320GB WD Scorpio Black 7200rpm)
8x Super-Multi DVD±RW
Creative X-Fi Notebook (ExpressCard) + Creative GigaWorks T40 Series II
Integrated 2MP Webcam
Dell Wireless 355 Bluetooth 2.0 Module
Intel Next-Gen Wireless-N Mini-Card
TV Tuner and Dell Travel Remote Control
4-in-1 Flash Card Reader (SSD/MMC/MS Pro/xD)
230W AC Adapter / 9-cell Lithium-Ion Battery
Windows 7 Home Premium (64bit)
Most people do not know that most laptop mouse pads are controlled by the software synaptics. That is the first step now we need to find the drivers, I am not aware of any previous drivers for the mouse being installed, by default even on a clean boot (meaning everything is new) there would be generic drivers installed along with the operating system. search.dell.com/results.aspx?s=bsd&c=us&l=en&cs=04&k=dell vostro 1710&cat=sup here is a list of vostro drivers for your laptop model this is another website that might help it has images which should be easier to follow. Basically
go to control panel -> mouse
mouse -> Dell touchpad
Dell touchpad -> Device select
Device select -> disable button
this information is coming off my vostro 1200 that I recently had to work on. I understand how much of a problem this is for most people I have to manage this problem more then most so I am sure this will work for you