The new Starcraft Terran Vs Protoss match-up has changed greatly since Starcraft 1. Now, as a Terran, you are much better off using Tier 1 units to cripple your Protoss opponent – Marines and Marauders in a tightly packed group is the bread and butter of this whole operation.
The use of M&Ms are usually your most effective strategy in the beginning stages of the game. Other than the Protoss Zealots, Stalkers can become a real problem for your platoon if they’ve been given the Blink upgrade. Do not let this discourage your early rush attack. The reality is, it will take a decent amount of time for him to upgrade his Stalkers (and Zealots for that matter). The only way for him to advance the capabilities of his Stalkers is by teching into a Twilight Council, and from there research Blink. Take advantage of this delay with a strong offensive push, and his Zealot and Stalker units will be no match for your M&M army.
In the event that your opponent makes the first move with his Zealots, you need to reinforce your base’s defenses with bunkers. These should be situated at the foot of your ramp. You want Marines to be guarding this entryway and a small group of Medics to provide secondary aid backup when the Zealots arrive.
But ultimately, no matter who engages first, you need to consistently force pressure which will keep the Protoss enemy on his toes – you do not want him getting comfortable at his base. Tech New Master
Once mid-game battle ensues, you can stick with the M&M units and build/tech up your Siege Tanks or utilize Siege Tanks, with Marines and Ghosts. With respect to your Siege Tanks, they are very effective in the Terran Vs Protoss Starcraft 2 match-up, and must be harnessed for maximal damage. They can easily destroy Tier 1 units from your Protoss enemy when in Tank mode. However, they must not be taken for granted – the cost to build one should encourage you to micromanage and position it properly. And if you’re facing heavy enemy fire, place Marines at the front lines so you can slow down your Siege Tanks’ impending destruction.
If you’re going to make use of Marines and Ghosts, the most effective way to prepare is by mining obscene amounts of gas. In this strategy, your Marines will defend against air raids, your Ghosts’ use of EMPs will significantly weaken the opponent’s shields, and your Siege Tanks will follow through with a strong clean-up attack. This works great but is hard to master.
As your resources begin to widdle down, make sure you’ve expanded your mining operations and established a second (or third) base. In order to defend these expansions, produce Hellions, Marines, and Siege Tanks. As your SCVs and Mules mine the minerals/gas, generate a small army of Ghosts to engage the enemy’s base. Then you’ll want to reinforce your Ghosts with increased Tank production. In order to do this you will need to build another Refinery.