I'm looking to do an install of Sharepoint Foundation 2010 and implement a Help Desk / Issue Tracking system.
This Help Desk Template is for Sharepoint 2007. Could I use it under Foundation 2010...?
Well, that's a bit of a tricky situation. If you have a current SharePoint 2007 environment with that template installed, you should be able to upgraded it to SharePoint 2010 without too much issue. But if you have a new SharePoint 2010 environment, you will not be able to create new sites using that template in the 2010 environment. This post has more info on that situation: http://blogs.technet.com/b/tothesharepoint/archive/2010/08/18/sharepoint-2010-products-upgrade-and-the-fabulous-40-application-templates.aspx
There is good news though :) A member of the SharePoint community has recompiled several of the site templates in that "Fantastic 40" group for SharePoint 2010 and posted them here: http://techsolutions.net/Blog/tabid/65/EntryId/17/Fab-40-Templates-for-MOSS-2010.aspx
I would suggest taking a look at that page and trying the Help Desk template you find there. It is important to keep in mind though that those templates are not supported, so you're going to have to deal with any errors or issues you encounter on your own.