syuumatu ni hutatu no resutoran no azi wo kuraberukoto ni simasu.

The phrase 動詞辞書形 + ことにする means “to decide to (do something).”

• 比べることにします literally “I will decide to compare.”
• In English we’d simplify it to “I’ll compare…”
• If you use the past tense ことにしました, it means “I decided to…”

The particle に marks a specific point in time.

• 週末に = “on the weekend.”
• Without に, 週末 can work more like an adverb (“weekends” in general) but with に it pinpoints “this coming weekend” or “on weekends.”

Japanese uses counters when counting objects.

• 二つ (ふたつ) is the general counter for inanimate objects.
• You attach の to connect it with the noun: 二つのレストラン = “two restaurants.”

The particle の links nouns to show possession or attribution.

• 二つのレストランの味 = “the taste of two restaurants.”
• First の connects 二つ and レストラン, the second の connects レストラン and 味.

Because you’re nominalizing the action with こと, the verb stays in dictionary form:

• 比べる
  • こと = “the act of comparing.”
• Then にします attaches to that noun phrase, so you need the base (dictionary) form.

No. You need こと to turn the verb phrase into a noun before using にする.

• Without こと, 比べるにします is ungrammatical.
• Always: 動詞 + ことにする or 動詞 + ことにした.