gear selection problem

Hi, I have a 2002 1.8 petrol, it can be real difficult to get into 1st and 2nd sometimes and often pops out of reverse. The slave cylinder popped a couple of weeks ago, which I've now replaced, along with a new bracket. I've read that if the clutch pedal is more than 20mm below the brake pedal then gear selection can be hard, mine is about 30mm, it suggests a new pedal. Before I fork out 60 quid for a new pedal I wanted to see if anyone has found that it has solved the problem, and why, as I can't see how a new pedal will allow me to press further onto the master cylinder.

Cheers

Was the clutch release lever freed up? If not that's a good place to start.

I've had the car 6 months it seems the same now as it has since I've had it. The problem with first and second is only after the engine has warmed up.