I'm about to buy a notebook for my university (informatics + physics) and I have a couple of doubts.

1. I've seen Asus T200TA with its touchscreen and it seems impressive. I'm wondering whether I shouldn't buy a touchscreen laptop for myself. Or maybe a matte display would be a much better choice?

2. Is it worth to pay about 100 EUR more and get an extra SSD drive (e.g. 128 SSD + 1000 HDD instead of only 1000 HDD). Keep in mind that average salary in Poland is ~1000 EUR and minimal - ~400 EUR, so we can approximate that tech products are 4x more expensive than in Germany or the US. Or maybe it's better to install the SSD on my own (is it possible at all?)

3. Does one really need more than 1366x768? Most of the notebooks I found use exactly this resolution.

4. As for the size - would you recommend 15.6"?

I'm planning to run exclusively Linux. (So I'd rather avoid buying a notebook with Windows preinstalled and later on fighting for the refund for an unaccepted EULA). I want the notebook to be versatile. I'll probably do a lot of programming in the future.

Besides, people from Poland: do you know any good place to get a notebook with Linux/without OS? Took a search on allegro, ceneo, x-kom - anything else?

i can answer about SSD: for 100 EUR you can buy good 200-256GB SSD drive. But instead you cann buy good 500GB-1TB SHDD with integrated 40-80 GB of SSD and you can install any linux here, and it will work perfect fast And screen resolution bigger than 1366x768 gives you absolutely different experience, and it's awesome, but beware, it costs much bigger if you broke it, for example default 1366x768 LCD costs about 30-40 EUR, 1920x1080 LCD costs about 100-120 EUR. I'm talking about panels w/o touchscreen.

Just my opinion:

1) I would go for matte display instead of the touchscreen. I had had a touchscreen laptop from HP for a few years, but hardly used the touchscreen itself. Now I changed for matte display and it seems like a better choice.

2) I would definitely go for an SSD - at least for the system partition, it's a small miracle.

3) I'd say 1366x768 is more than enough. The only time I've felt I'd use more was when using the SailfishOS emulator (540x960), but who uses the emulator for development anyways

4) My favorite size is at around 12" for the mobility, but it depends on the use case, so it's up to you.

By the way, if you're a Linux user, try considering ThinkPad. I got myself one (X220) and pretty much everything works out of the box, so it feels like heaven compared to my previous computers.

100% agree.

Regarding the SSD, go for it if you can afford it. I can't but I could at least afford a hybrid. Makes booting a bit faster but since I hardly ever switch it off I do not get much benefit from that.

And what about the IdeaPads? I was thinking about some Dell - 15 5558, Latitude 3550 or some Vostro 3558, all of them with 2 graphical cards.

Does Express Cache 8GB indicate a SSHD?

Im the hybrid junkie here, and I will tell you don't get a hybrid.
Buy a decent laptop.

13" 1080p Matte display (non-touch)
Core i5 dualcore is plenty fast and efficient
Get a minimum of 256GB SSD, or a HDD with 1TB+80GBSSD combo
Look for plenty of ports
Look for a BIG battery
The integrated Intel GPU is very efficient and powerful enough for everything

...except gaming.
There's some really good Mobile GPU's out there, particularly from nVidia, but I suggest against this.

If you want gaming buy a PS4. Or build a PC Gaming Tower.

I hope this could be useful.

Besides, will a H-HDD/SSHD work as expected in Linux? Isn't it Windoze-software-only?

I second the recommendation to get a ThinkPad - and I mean a real ThinkPad, so one of the t, x or w line, not IdeaPad or any other line from Lenovo that just makes use of the ThinkPad name while not providing the expected quality and features.

As you are working with a limited budget I would actually recommend buying a refurbished older ThinkPad model (t410/t510/w510/t420/t520/x220/etc. - but not necessarily the t440/t540 due to the unfortunate thouchpad choice). You will generally get something better & more durable for the same money that will get you a new but crappy notebook.

The H feature of the SSHD is completely transparent to the OS.

Too bad you didn't gave us your budget. But I would definitely say to buy a Dell XPS13 (very small form factor, really good screen, SSD, etc) and well supported by Linux.

Buy it Windows, always useful when you'll need to sell it.