This is a geosynchronous satellite though, so in theory it could go straight up if launched from the equator under the spot it wanted to end up at.
You'd still need to speed up perpendicular to the Earth, but you could in theory rise up in a straight line.
No, you can't.
Simplified description of what happens if you try:
http://wiki.kerbalspaceprogram.com/wiki/Maneuver_node#Radial_and_anti-radial
Radial/anti-radial burns (straight towards or away from the body you're orbiting) rotates the orbit around the craft (the link uses the example of spinning a hula hoop on a stick). If you burn directly upward from an orbital launch center, your orbit will be bringing you back to the launch point, which means a fiery reentry and crash. "Fiery reentry and crash" is the normal outcome of applying common sense to orbital mechanics.
There's no cheat code for an orbit. To get a roughly circular orbit takes a second burn at apogee after launch, or our perigee will still be down near the launch center, which ends badly for you. Generally there's a two ways to get to geosynchronous orbit with the fewest steps (Delva-V is lowest from an equatorial launch, but you can't ignore steps):
1. Launch to LEO, and continue the circularization burn until perigee rises above apogee, creating a new apogee at more-or-less the target altitude. Then at that apogee, a second circularization burn to raise perigee to the same altitude.
2. With a larger launch vehicle, launch into an eccentric orbit with apogee at/near the target altitude, with a single circularization burn.
Most of the time, method 1 is used, and the circularization burn and ascent burns aren't combined, because launch windows for earth orbit are more forgiving than ascent windows. Instead you'd park in a low orbit and then use two prograde burns (a Hohmann Transfer) to ascend to the target altitude.
In theory you can do it all in one continuous burn. It's a complicated low-thrust burn, and it still follows the same profile with less distinct intermediate stops. It's still not a straight up point and shoot - that'll either put you in a heliocentric orbit or on a path to fiery reentry and crash.
