You're one of those that thinks they've won the lottery when they get 37 shots on a 36 exposure roll, aren't you...lol
You don't need to spend 2k on a dslr, £100 will pretty much do it.
I do understand that its the content (grand kids) that matters, not what its shot on, the shooting film and budget lenses thing seems a completely separate interest.
M42 is a bit like that, million dollar pictures with cheapo glass, but you're gonna struggle with Nikon and its even tougher with AF.
Maybe if they'd fannied about with mounts and made half their range obsolete a few years ago, there'd be lots of bargain basement glass about.