[Bruno]

Re Combat:
A safe place to start when easing new players into new characters with a new GM (yay that new car smell!) is some fantasy classics.

The following suggestions are using resources you already have, as that's actually a pretty sound place to start.

Animals (or animate but animal-stupid plants) are a really good place to start because they have low DR, can't Parry or Block, don't need to have crazy smart tactics, and don't do Swing damage.
Dire Rats are a classic, and should be used in large numbers. 10 to 15 is a decent number. Note that they're not totally stupid, and should start running away into smaller tunnels if hit. This means you can use more rats!
Dire Wolves in a number roughly equal to the PCs (plus one or two) should be fairly easy for them to deal with, even at 150 points. It's a good introduction to fighting a modestly powerful enemy in equalish numbers. The wolves are high mobility, so they will need an open space to move around in to harry PCs, and should use that speed run away if significantly injured.
At least, if you want to try and establish that monsters won't always fight to the bloody death - you do that early if you want that, because people are usually conditioned by videogames to expect all enemies to fight to the death. If you don't want that, consider that you'll probably need to use less monsters, because they'll be involved in the fight longer.

One crushroom in an outdoor area with trees that combatants need to navigate around, underbrush to get tangled in (and for the Crushroom to plow through willy-nilly) is a good introductory fight for many PCs one big monster tactics (which should generally result in the one big monster being surrounded and hacked to pieces, or kited around in an open area while people kill it with ranged attacks) but it should also teach them some respect for monsters with 4d crushing attacks, 40 HP, and Homogenous (no vitals, no brain, no impaling bonus damage...)

And then you can always just take the low point templates from Henchmen, et voilla, bandits. They can be upgraded with racial templates from DF3, too - a bunch of Dark One guards and initiates with an Ogre Brute is more colorful, and more dangerous.