VA loans require a higher score, 640 I believe. But you could qualify for an FHA loan. VA has some great benefits, though. You may want to wait until you get a little higher. A credit card would do that, but you may need to get a cosigner. Or you could get a prepaid credit card. Just make sure to use the credit card to benefit your score, they can also hurt.
Check out my Trulia blog on credit card usage.