#1
currently im using a vox vt100 amp and tho the distorted/high gain amp models are alright-ish i cant help wanting a little more gain out of the thing to suit what i play.

all i have pedal wise is a boss ds-1 from back when i very first started playing and a pretty old zoom multi effects board. both sound terrible put through the amp on the clean amp models with the gain low and when i use them with high gain on the amp theres that horrible, way too much gain, squeecky, aweful sound - even when not playing.

so i was wondering: if using high gain models on the amp would i be able to knock up the sound slightly with something like a TS9 or equivalent, possibly something crunchy (my knowledge of pedals is minimal) without getting horible hissing and feedback?
#2
unless the amp is a tube amp, you dont have much to overdrive/boost

it is really tough to put a pedal through a modeling amp. but, i would seriously reccomend an mxr fullbore. im not going to be like most ppl on here and just tell you to get a new amp but if your looking for something with more gain, your not going to be able to find it with a modeling amp. i had the same issue with my peavey vypyr, and that is y i upgraded to a tube amp.

but, back to the pedal. i reccomend the fullbore simply because it has such a large possibility for eq'ing. it has a bass, middle, treble, level, frequency and gain knob as well as a built in noise gate (very helpful wen playing at high volume with alot of gain) and there is a scoop function that scoops out your mids for more of a heavy metal tone. the mids that r scooped is adjusted by the frequency knob.

this pedal has ALOT of gain on tap. for example, with my amp at quarter volume on the clean channel, my settings r

level: full
frequency: N/A (i used to always turn my mids down but they really help cut through the mix, so i dont scoop my mids)
gain: 10:30
bass: noon
mids: 1:30
highs: 3
noise gate: on
scoop: off

this gives a really nice, high gain metal tone, and the gain isnt even halfway up.

this guys english isnt great, but its a really good display of the pedal and its tones.
http://www.youtube.com/watch?v=GmJUaRNPS-0&feature=related

hopefully this helps a little bit