A 1080 monitor will do just fine. Most software runs in the PAL scan rate used in European televisions so a VGA monitor won't help you much unless you get an expensive scan-doubler.
In order to program an Amiga in C you'll need the Amiga Developer CD if you can find one. Version 2.1 is the latest for the classic Amigas. Beyond that I'd reccommend downloading
VBCC as your compiler since it has fewer bugs than Storm C++ version 3 that comes on the Developer CD.
Once you get your A1200, the first upgrade you'll want will be some sort of accelerator card since there is no RAM expansion sockets on the motherboard. If you can find a Blizzard 1230 that will do well. Put about 16+ megabytes of memory on it and you will do well.
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