Like others have said:

AVG 8 (just use that - it will have the least interaction with the user)

Firefox with adblock

GMail

Foxit (again, doesn't ask for any interaction and is speedier than Adobe)

VLC (just install it with every option, and it will handle every media request that's asked of the machine - no codec headaches)

Lastly, either install only Word/Excel, or install something like AbiWord. Don't complicate the machine with installing extraneous programs like Access. Then clean up the Start > Programs menu to take out unneeded links.

I just set up a system for someone's tech-wary 85 year old parents, and the idea was similar - set it up so as little can freak them out as possible, and put on programs that do basic tasks well or cover most conceivable situations.

To finish up, I'd enable the quick launch toolbar, and put the links to Word, Firefox, GMail (specifically), and whatever other important programs in the toolbar, on the desktop, and in the Start menu (not Start > All Programs, but the Start menu its self).

*edit*
For remote control apps, check out this top-five summary (based on voting by readers on that site). Looks like TightVNC will do Linux->Windows.