Not much I can add to Kano's answer, other than to say it depends on how you define climate (time-wise). The emissions from some volcanos have a very long lasting effect. But, in general, yes - large volcanos will have a quite noticeable effect on global temperatures.

I guess two things I could add.

1) There are many natural processes that will have a noticeable influence on global temperatures. Some of them will have a larger effect than AGCC. Otherwise the curve of global average temperature would be mostly straight up. The difference is that these natural signals are either cyclical (e.g., solar input), or impulses of relatively limited duration (e.g., sulfur emissions from volcanoes).

2) This exact process (sulfur compounds reducing global temperatures), is part of a climate mitigation proposal. Seeding the atmosphere with large amounts of sulfur to reduce global surface temperatures has been proposed as a way to give humanity more time to deal with AGCC. Of course, it is rare that any kind of attempt like this doesn't have unintended side-effects. Perhaps worse than the original problem (see kudzu).

Yes. sulphur emissions from volcanoes, have in the past altered Earths climate.

The Tambora eruption in 1815 caused 1816 to be called the year without summer, and the Toba super eruption is thought by some to have nearly caused humans to become extinct, even Mt Pinatubo had a measurable effect on our climate.

https://www.google.com/#q=Mt+Pinatubo

Global temperatures decreased a fraction of a degree for several months.

And Pinatubo was a very large eruption.

Yes but only by 1 degree Celsius. So it would hardly effect anything long term.

Only in the immediate area. It would take the eruption of many volcanoes to cool the earth very unlikely to happen