Playing T&T with D&D adventures-Help

What kind of D&D? One of the modern kinds or an older version?

I have hundreds of adventures and some very new to rpg people to play with. I could just play 1E D&D with them but I think I finally found people who would love T&T as our main game so...I want to take advantage of that.

I suppose it would have been helpful to mention how to decide on the MR...use the average number of dice the delvers will be rolling as the MR.
If orcs with short swords get trounced too easily then the next batch will have long swords, then battle axes then bazookas...ok, no bazookas but throw in a shaman with TTYF just to keep the delvers on their toes.
There is no need to calculate each orc and weapon, a vivid description will justify any amount of dice you decide to throw as well as any special effects the delvers need to save against.

This is excellent advice, and it's what I do when using materials for other games with T&T. In 4th edition, setting MR = HP is a useful rule of thumb, but setting the MR based on your own goals (and/or the delvers' goals) for each encounter is the best way to go.

I have used the formula from M6E to determine a basic challenge level for each encounter:

1. Add up all the delvers' attack dice and multiply by four (the real average is 3.5, but I use spite damage).
2. Add the delvers' combat and weapon adds to the above total.
3. Go ahead and add the delvers' combined armor value. The total of the above is the delvers' average HPT for one round of combat, without factoring in the infinite variation possible with spells, stunts, good or bad tactics, and good or bad role-playing.
4. Now set the combined MR of the opponents equal their average HPT with a multiplier based on how tough you want the enemy to be: it can be anywhere from CPT x1.15 to CPT x1.5 or higher. Also remember that giving a monster special abilities, armor, MR-independent hit points, or canny tactics can make monsters a whole lot tougher.

I don't actually follow this formula for every encounter, but it's given me a good metric for gauging the challenge. In reality, delvers can radically alter the "balance" by convincing foes to surrender or flee, or by any number of good or bad tactics.

One thing to note is that low-level enemies can still pose a meaningful threat to T&T delvers, especially if they come out in force with good tactics, and especially if you're using spite damage. Don't worry about scaling up every encounter to provide an adequate challenge-- if they have an easy time, let them: they're learning the game. Also, don't worry too much about having enemies that are too tough-- sometimes they need to learn to run away, and creative players will surprise you with canny tactics and stunts to bring down even your most dreadful monsters.

I found a couple of threads that might be helpful.

This thread has some good stuff in it, although the link in the first post is broken.

This one also looks good and has some thoughts on similar D&D monsters converted into both 5E and 7E.

I'm pretty sure that there are others as well. It's a popular topic!

Awesome replies guys! Thanks!

Try this: www.igsgames.com/Utilities/MRCalculator/

Set the menus to what you think the average character will look like, and it will pop out the MR that has a 50/50 chance of beating that character in straight up melee. Scale up for the fact that the characters have missile weapons, spells, and other tricks. Scale down because the characters will have to fight multiple combats. Fudge as required.