As far as SSD is concerned , never had one u think it ll help loading D3 maps etc ? Any budget suggestion ? (small size just to load win7 and 2 - 3 games) How i check if my mobo is compatible ?
OH YES. Load times in D3 go from "let me go make a coffee in between switching rift levels" to "oh wait, was there a loading screen"? Obviously a little bit of an exaggeration but it's really noticeable. There's no "compatibility issue", it uses the same SATA connector that other HDDs use; the only restriction might that your mainboard doesn't support the speed of an SSD (which is really through the roof). Budget for hard drives is difficult, because if you go a bit smaller (say half the size) the price doesn't drop by half the size but just by 20-30% or so. Best bang for your buck currently offer 250 GB HDDs, a really good choice is the Samsung EVO 850, 250GB for around 80-85 EUR. The cheapest ones in that size start at around 65 EUR whereas the cheapest 120GB ones start at 55... so it's not really worth it, in my opinion. Especially because OS + GTA V = SSD overfull at 120 GB
Such a terrible moment for your GPU to bite the dust. I recently looked into potential upgrades and decided currently it's a no-go. I personally would strongly recommend to settle with a rather cheap solution that'll be enough for your current gaming needs for at least a few months, and then hope that Bitcoin crashes or the bubble bursts or in some other way this madness ends.
For those who're not aware - graphics card prices are currently doubled because cryptocurrency miners are buying them left and right to put them in their racks for mining Bitcoins. While there's no immediate solution on the horizon one can only hope that this will not be a permanent state of affairs and prices go back to normal in a while.
On topic: I don't know how high the GPU demand of WoW is and I have no idea what WoT is, but I doubt HS requires any high GPU power and D3 runs super smoothly on my 960 GTX. So unless you plan on playing the absolute newest shooters and every game in full HD ultra high settings with 16x AA, I'd say saving a few bucks right now and settling with a lower choice might not be the worst idea. I always like to start my search by checking logicalincrements.com for a comparison of "reasonable choices", and then go from there. I think which one exactly you settle for also depends on if you can get a good deal.
Besides, if I was you I'd also spend some money on an SSD, as I didn't see one in your list. An SSD is an absolute must (especially for D3 it really helps a lot).