You might want to check out the Boss OD-20 if you want distortion / overdrive. I have one and it is a good buy.

I also have the new Boss flanger (BF-3), though I think I prefer the BF-2 (I had 2 of them !). The Boss phaser is one of the nicer ones I have tried however beware of the Autowah and the pitch shifter (both of these are currently sitting in a draw rather than in my pedal board). I use the Dunlop 535Q wha and really like it. Previously I have had the standard Dunlop Wah and still have the Hendrix Fuzz-wah (back in the UK). The 535Q is currently my favorite.

I plan to get a Digitech Whammy (which is another really nice pedal) to replace the Boss pitch shifter.

I also use the CE-20 (double chorus), RV-5 (digital verb), DD-6 (delay), CS-3 (pretty crappie compressor) in my setup at the moment and on the whole Im quite happy with it.

Other cool stuff:
Boss CE-5 Chorus. Very vice, Boss MZ2 metal zone, very nice but not as versatile as the OD-20. Ibanez TS(3?)DX turbo tube screamer. This pedal was not for metal but still sounds very nice. Again the OD-20 nails the sound perfectly.

Stuff to avoid:
really budget gear called Maxx, avoid it like the plague. Also the Boss GP-20 amp factory was an absolute disaster. I also got burned by using the Boss GE-7 EQ though that was probably because of the other pedals I was using as well. Needles to say it found its way onto eBay. Ibanez tone-lock (snicker) distortion pedal (the grey one). Sounded as bad as the tube screamer sounded good. I ended up giving this one away.