Great suggestions Pashmina. I would definitely go with number 1, this should be able to do exactly what you want since you can set the ad scheduling to 0 on days you don't want.

I would hesitate to automate it by telling Adwords to optimize for conversions. I haven't had good luck with this in the past and it take a while for Google to get a handle on what converts and what doesn't, so you might have terrible ROI for a few weeks.