One important bit of advice I haven’t read here yet is to make sure to check the “expense ratio” of the fund you pick… this is the haircut you pay each year for the management of the fund. 1% a year might seem like a little, but through the miracle of compounding, it really eats up your long-term returns.
(I like “index funds” because they tend to have the lowest fees. My current 401(k) has an enormous quantity of high-fee (some almost 3% a year!) choices, and *one* index fund (Vanguard 500 Index (VFINX)). That’s where I am.)
That said, I would save as much as you can now, however poor the options, because when you leave, you can move it all into an IRA and then make whatever choices you want. (Also, in 2010, you’ll be able to convert traditional IRAs into Roths, with no income limit. Check out Suzie Orman. Sweet!)