Yes, there should be a shut off valve in your front yard at the water meter that you might need the long T-handle wrench for. You might also just be able to use a pair of pliers if the valve isn't too deep or too stuck. Be warned that you probably don't own that outdoor fixture (the water utility should) and you're gonna be screwed if you break it. If you have any doubt, hire a licensed pro.
The gate valve in your basement can possibly be rebuilt depending on the reason it doesn't fully close anymore. You'll still need to kill the water at the street first.
A full flow ball valve (has a 90* lever instead of a round handle) can be swapped in for the old gate valve. You can research the differences in the two and decide for yourself. Personally, while I generally like PTF fittings, I would lean towards a traditional, sweated connection for a main shut off since the fallout from a failure can be catastrophic. You will need to consider the type of existing valve, access, how much play you have in the main line*, and the size (length, not just correct diameter - see *play) and type of the replacement. You'll also need to know how to correctly sweat a fitting and do it safely around wooden structure! If you have any doubt, hire a pro.
This should be the kind of job where you'll be pissed at having to pay for such a fast visit from a pro but peace of mind is worth something, too. Reading back over this, I'm sorry if it seems that I'm implying you can't do this. If you're the kind of guy that Murphy never calls the law on then you can easily handle this. But if your headlights stopped working after you checked your tire pressure........