One thing to note is that freeplay will not generate a W-2G. Of course, you are obligated to report your net cash winnings after you run the freeplay through a machine, and if you happen to hit a jackpot on the machine that pays $1,200+ you will get a W-2G from that.
The requirement is that you need to run the promo money (freeplay or promo chips) through one time. So you are only obligated to subject the money to the house edge one time. You may need to manually track your play (for machines) to know when you have played it all through. And as noted, make sure that any chips are of the "keep until you lose" variety, or you are effectively getting only 50% return (actually 50% - the house edge). If you can get the right type of chips, then Baccarat or craps is a good choice for using the chips. Blackjack is an even better choice, but only if you are willing to invest a few hours to learn basic strategy, or to print out a table from the interwebs.