Learn Spanish (Latin America): Si el programa que usamos se bloquea, apago la computadora. - If the program that we use freezes, I turn off the computer.

Yes! In real conditionals (situations that are likely or normal), you use si followed by the present tense for the condition. For the result, you can use the present tense (apago - I turn off) to state a general fact or routine, or the future tense to say what you will do. Both are correct!

Why does the sentence use se bloquea instead of just bloquea?

Bloquear normally means to block someone or something else. When a computer program freezes, crashes, or stops working on its own, Spanish uses the reflexive form bloquearse (literally, it blocks itself). That is why we need the pronoun se here.

Can I leave out the word que like we sometimes do in English?

No, in Spanish you can never skip the word que (that/which) when linking ideas. In English we can say the program we use, but in Spanish it must always be el programa que usamos (the program that we use).

Is computadora the standard word for computer in all Spanish-speaking countries?

In Latin America, computadora (or computador in some countries like Colombia and Chile) is the standard word. However, if you are speaking with someone from Spain, you will hear them say el ordenador instead.