When you say "turns on" I guess this means the engine turns on normally but you can't put it into gear. There is a switch under the clutch pedal that lets you start the engine only when the clutch pedal is down. So far, we know this is working. Normally I would say a stuck shifter or non engaging shifter is caused by the shifter assembly on top of the transmission but you say the clutch pedal is stuck.
From easy and more obvious to harder and more expensive...
First idea, clutch fluid is dry or low. Does pumping the pedal do anything? It's not safe to drive in this condition. Open the brake fluid/clutch fluid (they share the same reservoir) and see if it's at least at min. You cannot just add fluid since air got in the lines. See this FAQ:
http://www.myturbodiesel.com/1000q_how_to/a4/brakeclutch%20fluid.htm It's for the mk4 cars but it's almost identical. You must add fluid and get out the air.
Other idea - clutch pedal is broken or the clutch pedal linkage to the master cylinder or to the clutch pedal is broken. Look under the dashboard at the pedal cluster, it should be obvious. If you see fluid leaking from around the clutch pedal linkage, the clutch master cylinder has blown a seal.
More difficult - these are things that you can't see with a quick inspection but could cause the clutch pedal to get stuck on the floor. Clutch slave cylinder (follow the clutch fluid line to the cylinder on top of the transmissino) has failed or is leaking. You have to unbolt it to inspect. Clutch fork, pivot ball, or clutch/pressure plate is having a problem- this will prevent the clutch slave cylinder from doing anything. These require transmission removal to fix. See the transmission removal FAQ for pictures of these items.
In an emergency, (advanced technique for real emergencies where you cannot get help), put the car in first gear with the engine off. Start the car and hold the ignition to get the car moving. Once it's moving, drive until the normal speed for 2nd gear. You can upshift without the clutch as long as the engine rpm is matched. You can also "feel" the shift lever slip in. Don't force it because it won't work. Shift as needed. When you get to a red light, shut off the engine and start again. I recommend first practicing this on a level road with no traffic to try it out. You should always be rev matching to minimize transmission and clutch wear and for smoothest shifting anyways. Of course you want to use the clutch for normal driving, again, this is just an excercise to learn this technique and make you aware of engine rev matching to improve your normal driving.
Good luck.