ok ladies... talk to me about mountain bikes, please!

[DirtDiva]

I'm no Specialized expert (have never even ridden one), but thinking back to my recent bike shopping browsing I'd say the geometry is similar and the rockhopper comes with a better spec than the hardrock. I'm sure you can check it out at the Spealized site.

As far as Shimano components go, XTR/XT is top notch, LX/Deore are next and Alivio/Altus/Acera are the more entry level stuff. They have a few other categories, but those are the ones you're most likely to see on whatever is in your LBS. Some bikes will have components made by SRAM. I guess they make quite good stuff, because they tend to be on more expensive/higher end bikes.

You will need a smaller mountain bike than road bike as you generally want a bit more standover height and it's really hard to get the front wheel off the ground if the top-tube is too long. Most companies go down to about a 15 inch frame: if I remember correctly, you're not that tall, but if you're a real shortie you might want to look at Gary Fisher, Giant, Kona and Marin as they are all decent enough brands that make extra small frames. You're shopping at a good time of year - the sales should be coming up!

Most importantly, remember that dirt is good! (Hmm... May have to have "dirt is good" as my sig file...)

Hope that all helped. Have fun!