Is there anything that Windows can and GNU/Linux can't in Web programming and design?

It can crash in the middle of your unsaved work.

I think Adobe photoshop is not natively supported under Linux which is an issue for some web designers I guess. I've read articles about Adobe working on better support for Linux though. I think you need to specify your question a bit but my short answer is no.

Can't GIMP do a job instead of Photoshop?

What I need is: PHP, HTML, CSS - nice-looking (in Windows first of all) dynamic Web-pages. I want to develop them in GNU/Linux, without Windows and any other shareware.

You can use GIMP and you should be fine with it. PHP, HTML and CCS should be no problem to develop under Linux. I don't think the operative system matters as much as the users web browser. So you can even test with most of them in linux too. I normally testview with all browsers I have available.

While I love The Gimp, it's no Photoshop for sure. Other than that, there should be very little that would hold you back.

I have been trying to find tools similar to what I use in Windows on Linux also. Although you will never hear me speak ill of Linux for server use, desktop use, or many other functions this is the one spot that I personally feel Linux or more specifically Linux applications fall short.

I use most of Adobe's suite for my web design, (Adobe Photoshop, Dreamweaver, Fireworks, etc..) and although GIMP is a REALLY nice editor, it surely is not Photoshop. I am yet to find anything close to Dreamweaver as well.

So far I have played with some HTML editors, SeaMonkey works,but kind of reminds me of a replacement for FrontPage, if anyone remembers that.

Stick to windows for web design. Let Linux run the back end (LAMP) like it was meant for until someone like Adobe starts porting over this apps.

I agree that Adobe has a very expensive suite of tools that are hard to beat.

Re HTML editors, have you tried eg Bluefish v Qanta Plus v NVu http://ubuntuforums.org/showthread.php?t=842808.
Not my area of expertise, so have a look.

I was also going to suggest bluefish. It is very similar to dreamweaver. If you don't need a WYSIWYG editor though you could do your html, php and css in vim.

But alas, I also use Fireworks

I am partial to bluefish

And photoshop works perfectly under wine. at least for me. using cs2

+1 to themanwhowas using vim for html, css and php