Если курсор не двигается, лучше перезагрузить компьютер.

Если means if and introduces a condition:

• Если курсор не двигается = If the cursor isn’t moving

This is a normal conditional structure in Russian. It sets up the situation under which the advice in the second part applies.

Russian normally uses a comma before or after a subordinate clause introduced by words like если.

So in:

• Если курсор не двигается, лучше перезагрузить компьютер.

the comma separates:

1. the if-clause: Если курсор не двигается
2. the main clause: лучше перезагрузить компьютер

This comma is required in standard writing.

Both forms exist, but they come from slightly different verbs:

• двигаться → двигается
• движется is an older/literary-style form related to двигаться

In everyday modern Russian, двигается is the normal, natural form for moves / is moving.

So:

• курсор не двигается = the cursor isn’t moving

sounds like standard spoken and written Russian.

Because the verb here is двигаться, not двигать.

• двигать = to move something
  
  • transitive: it takes an object
• двигаться = to move
  
  • intransitive/reflexive: the thing itself moves

So:

• Я двигаю стол. = I’m moving the table.
• Курсор двигается. = The cursor is moving.

Since the cursor is not moving by itself, Russian uses двигаться.

Here лучше means something like:

• it’s better
• better to

This is an impersonal construction, which is very common in Russian. Russian often leaves out a subject like English it.

So:

• лучше перезагрузить компьютер
  literally: better to restart the computer

More natural English:

• it’s better to restart the computer
• you’d better restart the computer

There is no explicit subject because Russian does not need one here.

After лучше, Russian often uses the infinitive to give advice or suggest the best action.

Pattern:

• лучше + infinitive

Examples:

• Лучше подождать. = It’s better to wait.
• Лучше проверить ещё раз. = It’s better to check again.
• Лучше перезагрузить компьютер. = It’s better to restart the computer.

So the infinitive is exactly what you would expect after лучше in this kind of sentence.

Because перезагрузить is perfective, and that fits the meaning here.

• перезагружать = imperfective, to be restarting / to restart repeatedly / in general
• перезагрузить = perfective, to restart once and complete the action

In this sentence, the advice is about one complete action:

• restart the computer

So Russian uses the perfective infinitive:

• лучше перезагрузить компьютер

This is very common when giving advice about a single practical step.

Компьютер is the direct object of перезагрузить, so it is in the accusative case.

But for masculine inanimate nouns, the accusative singular is usually the same as the nominative singular.

So:

• nominative: компьютер
• accusative: компьютер

That is why it looks unchanged.

Compare with an animate masculine noun:

• Я вижу брата. = I see my brother.

Here the accusative changes form because брат is animate.

Yes. Russian word order is fairly flexible, although some versions sound more natural than others.

The original:

• Если курсор не двигается, лучше перезагрузить компьютер.

is very natural.

You could also say:

• Лучше перезагрузить компьютер, если курсор не двигается.

This means the same thing, but the focus is slightly different: it puts the advice first.

Russian often changes word order for emphasis, information flow, or style, while keeping the same basic meaning.

It is advice, not a direct command.

• лучше перезагрузить компьютер = it’s better to restart the computer

This sounds softer than an imperative such as:

• Перезагрузите компьютер. = Restart the computer.

So the sentence suggests the best action rather than ordering someone to do it.

Yes, but the meaning changes.

• Лучше перезагрузить компьютер. = It’s better to restart the computer.
  This is advice or recommendation.

• Надо перезагрузить компьютер. = It is necessary to restart the computer.
• Нужно перезагрузить компьютер. = It is necessary / one needs to restart the computer.

Надо and нужно sound stronger and more like necessity.
Лучше sounds more like: this is the preferable solution.

Yes. In Russian, the present tense can often cover both meanings depending on context.

So:

• курсор не двигается

can mean:

• the cursor isn’t moving
• the cursor doesn’t move

In this computer-troubleshooting context, English would usually translate it as:

• if the cursor isn’t moving

because it sounds like a current problem happening right now.