Good discussion, guys. I want to comment on bid/ask spreads. If you are thinking about "day-trading options", then trade only in options that have extremely good volume and a reasonable spread in the bid/ask prices. Otherwise, you'll have a lot of slippage.
To find options that meet this qualification look only at the most actives list for a few days. At that point you can make a list of about 10 most suitable candidates. You'll also want to have a pretty solid stock trading volume to support this, but I'm certain that is pretty well automatic for all the stock options you will have on your list. Don't confine yourself strictly to the DOW 30 stocks. You'll find others like AAPl, and NDX will also work well (even though the bid-asks are wide on NDX, they are supported on several exchanges and the market makers compete well). I have traded the NDX quite a bit and rarely had a problem with fills at 5 to 10 cents off the mid. I agree with Mark on the lot size--10 to 20 spreads are a piece of cake at virtually anytime, and more than that 90%+ of the time.
As for as options brokers go, TOS and IB are your best choices. IB has slightly better commissions (but charges for cancels, which I do regularly in search of a better deal). TOS support is outstanding--I've NEVER had any trouble talking to them and they will negotiate commissions if you do a reasonable amount of business.
Merry Christmas!!!