First time poster and complete noob to biking. I'm thinking of starting to really get into biking, and would mostly be doing short/medium distance rides down a canal path and other trails as well as commute a few miles to work and around town. I'd also like to take it offroad once in a while in local parks (nothing extreme). I currently have a old piece of crap big box store bike which rattles like no other so I've been on craigslist the last few days and came across a 2001 Cannondale Bad Boy ultra listed for 425. It comes with 2 sets of tires, one for MTB and the other road use. Seems a little high, but should this be something to consider if the price can be lowered a bit?

Cannondale Bad Boy

I've heard nothing but good things about Cannondales, but I don't know if this is just too much for what I need right now. I've come across some cheaper used Giants and Specialized which seem like they may offer similar performance for a little less money. Any thoughts or comments would really be appreciated, thanks for the help!