If you want to increase endurance for running I think the general suggestion is to hit the track and do running? Get your mile time down or similar.

In my personal experience I've found strength training better for losing weight than just cardio but any activity will help a bit. You'll really need to adjust your diet in some way for it though, or at least start counting and keep your calories steady as you do more activity. Trying to outburn what you eat takes like an hour of exercise a day otherwise, it's tough.