Wow - I don't think anyone read your posts, Vincent. 2% fully vested for a couple *months* of work in a company you believe in? How is this not a generous offer? I can't believe how many people are telling you this is a bad deal when you are stating you already know it's a good one.
Anyway, let's address your actual question: If they are offering common versus options, take the common; it's a bit cleaner.
If they are only offering options, ask the following questions before you ask for anything else:
1) When will the option grant occur by (date)?
2) What will the strike price be?
3) How many shares will 2% be?
4) What is your compensation if you do not receive the option grant on or before that date and at that strike price or below?
Make sure you get the answers as part of the contract. Then, you can do the math of multiplying the strike price by the number of shares. Since you'll be fully vested immediately, you can write a check for this amount back to them and you will own common shares instead of options instantly.
So, assuming this is a real small number and you can get all this in writing, I don't see there being much of a practical difference here. Basically you're just going to get paid a little less since they'll write you a check for your work, then you'll write one back for the equity. The only risk I see is that they do not make the grant in a reasonable time frame - but as long as your contract explicitly explains your compensation in that event (and you're happy with the alternative), that should be covered.
Since it seems like unsolicited advice is the norm for this thread, here's mine: try to only work with people you like and try to treat them generously when you do.