Originally Posted by BlazingPedals

I haven't seen anyone mention proper use of the gears. Keeping it in high gear does not make you go faster; it just makes it harder to pedal. Keep a low enough gear that your feet are turning 80-100 rpm all the time. Any time your feet get outside of that, feel free to shift up or down to regain the correct cadence.

As far as the wheel size, it really doesn't matter. Maybe the current bike is too big for you - which is a frame issue, not a wheel size issue. You should be able to comfortably straddle the top tube without banging any tender bits. Adjust the saddle so that it leaves your knees slightly bent at the bottom of the pedal stroke. This necessarily means that you cannot sit on the seat when your feet are on the ground. If that's a feature you want, you should look for a different style of bike, a cruiser, which puts the pedals further forward.

Your current bike is not a 26" bike, it has 700c wheels, which are roughly - but not exactly - the same size as the old 27" standard. If you only ride on paved trails and streets, you can always change the tires to something with more or a road tread.