Some ('98) A6 Quattro questions, incl. changing from U.S. speedo/odo to Canadian?

[Barton Oleksy]

I recently acquired a 1998 A6 Quattro Wagon from Wisconsin (thanks to 
lister Doug Y.!) and had it shipped to me here in Canada.  I'm very 
pleased with it so far, but a few questions/issues have arisen & I hope 
some listers can help.  (BTW, it feels like I've jumped ahead a 
generation or two from my '91 200TQ!)

1.  Canadianization issues (metric) - I have managed to change the 
climate control to display Celsius instead of Fahrenheit, but how 
difficult will it be to change the speedo to read km/h on the larger, 
more detailed outer ring & mph on the inner?  And what about changing 
the odometer to read in kilometers rather than miles?

2.  I get the "OIL" message flashing for a minute after startup, which 
according to the owner's manual means that the car thinks it's ready for 
an oil change.  What's the magic to resetting that so I don't keep 
getting the "OIL" message after I do the change?  My local mechanic said 
he can reset it for me, but I'd like to know how on my own.

3.  There's a button I can't find anything about in the manual - it's on 
the driver's side on the pillar between the front and back seats. 
Doesn't seem to do anything when I press it, but I'm definitely curious 
about it.

4.  Climate control system seems to work fine everywhere *except* the 
lower driver's side, on the legs.  There I get a slight draft, which is 
quite noticeable at highway speeds (and quite cold after a few 
minutes!).  Is there something I can check fairly easily on that, or 
should I leave that for a mechanic?  I'm not experienced with doing much 
of my own repairs, but I'm willing to give some of the easier things a shot.

5.  Cup holders.  I found the two cupholders under the middle armrest - 
not terribly handy, though, esp. for the driver.  Any suggestions on 
add-on cup holders for this year/model?

I can probably come up with many more as I keep discovering more about 
the car, but here are some initial questions/issues I could use some 
help with.  Thanks for any and all responses!

Bart