I've been looking into a mountain bike lately. I want high quality but I don't have much to spend either, many people have pointed me towards Trek. A few questions I have:

-What are the major differences between the 3, 4, 5, etc. series other than price? I don't know much about bike lingo or specs so their website is foreign language to me.

-If I'm willing to spend a little extra, are there any disadvantages to disc brakes?

Thanks!

Quoted: I've been looking into a mountain bike lately. I want high quality but I don't have much to spend either, many people have pointed me towards Trek. A few questions I have: -What are the major differences between the 3, 4, 5, etc. series other than price? I don't know much about bike lingo or specs so their website is foreign language to me. -If I'm willing to spend a little extra, are there any disadvantages to disc brakes? Thanks!

This might not effect you much. But here in Oregon, rain makes mud. Rains quite a bit on the wet side. When your rims are caked with mud, traditional brakes lose their effectiveness. I prefer discs.

I'm not familiar with Trek too much, I'm just guessing. The more expensive the bike, the lighter it is and the better the components, i.e. brakes, shifters, shocks, etc.

I can tell you I broke a Trek Y-bike in 2000.

Discs are the better way.  Rim brakes collect a lot of crap, too, and if you happen to bend a rim slightly a disc is not affected.

As it's been said above most bikes have better components (usually a higher standard and lighter) in their more expensive models of the same series.  Some need the lightest, newest and best.  I go with what I can afford, which has been a 1998 K2 5000 that I've had since 2001.  It's stuck with hydraulic rim brakes (no disc mounts), and will be it for me unless I break the frame/fork.  

They are a bit maintenance intensive if you put a lot of miles on 'em.  Various bearings, chains, bottom brackets, chainrings, and cassettes wear out with a fair bit of regularity, and cables and derailleurs need fairly frequent cleaning and adjustment...or maybe my stuff is just too cheap