i dont reccomend Digitech. at least definatly not their distortion. Digitech dist. is very fake sounding- very fuzzy and muddy. if you try it out, you'll see what i mean. it can sometimes get a nice sounding solo sound, but anything for rhythm sounds horrible. their mod effects are alright, but you can get something better elsewhere.

the boss dd6 delay is excellent, good choice there. I vote thats a definate.
their super chorus is pretty good too. boss in general is good quality.

I like multieffects alot, so I say go for the Boss ME50, and take care of everything in one nice package.
the Korg Toneworks AX3000G is also pretty good.

a good distortion pedal would be a MXR ZW-44 Wylde Overdrive.
I personally Love the Electro-harmonix Big Muff Pi.

as for wahs, I just have the crappy wah that comes with my Digitech gnx3. (which i dont really reccomend getting. it would be fine for beginners I guess though.) so im not really going to be much help here.