Although, I'm quite sure 4wd is nice to have, you can do almost anything with a 2wd tractor if you're careful. I've been using my Ferguson for over a year now. I finish mow, brush hog, use a landscape rake and backblade and tow a manure spreader with it (as well as many other tasks), on over 50 very hilly acres. I only got stuck once, this winter in a snow drift (and got out in 10 minutes). I immediately went out and got chains and never got stuck again.
As I said, 4wd must be nice to have, but some of us (myself included) just can't afford a newer tractor that has it. My 25 hp Ferguson has served me well, and I just bought a 55 hp Oliver with a loader to use in applications where my Ferguson is too small. This tractor is also 2wd, and will handle whatever I throw at it.
No one should be afraid of an older tractor with 2wd, as long as they realize that they have to be careful to avoid a situation where they can get stuck. I pull a large filled manure spreader over hills with my little 2wd Ferguson, and have never had a problem.