Playing D&D 3.5e - Can a ranger, paladin or even a rogue take fighter feats, providing they meet the requirements?
Yes, they can.
Any feat designated as a fighter feat can be selected as a fighter’s bonus feat. This designation does not restrict characters of other classes from selecting these feats, assuming that they meet any prerequisites.
(quoted from the srd)
You can always select feats you meet the prerequisites for
Peregrin Took’s great answer has a direct quote about this specifically for fighter bonus feats, but I wanted to expand on that and point out that any and all restrictions on who can take a feat will be found in two places:
the feat’s individually-listed prerequisites
(more rarely) the prerequisites for the feat’s bracketed type descriptors
So generally, you’re looking at the prerequisites. For all general feats, this is certainly the case—and most fighter bonus feats are “[General]” since “[Fighter]” isn’t a thing (instead fighter-bonus-feat status is listed in the Special section of the feat).
For a very few types of feat, there are more prerequisites hidden in the bracketed type. For instance, the Expanded Psionics Handbook’s [Psionic] feats can only be taken by psionic creatures. Book of Exalted Deeds has [Exalted] feats that are only accessible to those who maintain the “gooder-than-Good” exalted status. But these are the exception; most bracketed feat types don’t have “secret” prerequisites like this.
Either way, as long as you meet the prerequisites—both of the feat itself and of the feat’s type if any—then you can take the feat. There will always be something in the feat that indicates a restriction, whether it’s the explicit prerequisites or the bracketed type descriptor on the feat. There is never any limitation on who can take a feat (with their regular, 1st-and-every-third-level feats) beyond those.