LOL, I just found myself  what Deleted 2 is, - it's like… Electric Boogaloo! Thanks anyway, you're help is sweet - which you will find utterly offensive I trust  ( I'm slowly getting the hang of this site). I'll keep reading more before asking silly questions. No guaranties, however.

I've read about any tutorial at MTS, also the ones about changing Sims, simsurgery etc. but I must have looked over the warning or it simply wasn't there: that you should never delete from the neighborhood sims bin. That's exactly what I did. In SimPe I now have quite a few unlinked and ‘no character data' clones. I thought it wouldn't do any harm so I left them. But all of a sudden these deleted Sims started popping up as people they brought home from work. Later I had an invasion of gardeners that brought the game to a standstill. Only then I suspected that there was something seriously wrong. There are about 15 gardeners now in my game….
I think I know by now how I can safely get rid of them, the others (the clones without character data) are a different story, I wouldn't know how to get them back in the game in the first place. Besides, I don't know what ‘Deleted 2 ‘ is, to be honest.
Anyway, I think my hood is (eventually!) beyond rescue. I had some hopes that starting with a clean template, it   would be possible to just put my beloved Simmies back in, but now I understand they still will be infected with orphaned DNA, memories, wants&fears and what have you.
The only positive thing is that I don't let my Sims reproduce or die, so the DNA effects are minimal. I've done some clean up work on the memories part with the  "lot debugger" and the game plays remarkably well. For the moment that is. I hope until Sims 3 comes out….

Still, I'm very angry at Maxis for including this apparently disastrous option ( delete button in the bin ) in their game in the first place! There was no way for me knowing that something simple as that could wreck the game that much. I'm a careful player, made a lot of backups, don't have too many hacks installed and now it's Maxis itself that screwed up my game.

@Emma : I would, but I don't know what link you're referring to.

edit: You mean this tutorial I guess. O.K. I'll try that.
http://www.moreawesomethanyou.com/smf/index.php/topic,5861.0.html

Thank you so much for your answers. @Gwill: By saying ‘start over', I hope you don't mean ‘start over' - from scratch …, do you?.   By using the clean template method I can actually save my Sims and houses, right? Or am I dreadfully mistaken… For now I hope I'm not and presume that what will happen is that my Sims will loose all contacts with my Townies etc., which is a minor problem, I can populate and befriend my hood easily enough. I'm a bit scary and exited at the same time, it would be quite a job, but populating my (sub)hoods with self-made Sims would be a great advantage and definitely worth the effort. I suppose this is the best tutorial to follow?
http://www.moreawesomethanyou.com/smf/index.php/topic,5861.0.html
Some questions however:

1.Can I populate downtown and leaving the vampires out ( I never cared for them much), or is that something the game will make anyhow.
2. How about my businesses? By getting rid of my old townies, they will loose a lot of customers so I suppose my ranking goes down?
3. How do I go about moving my Sims to the new cleaned N.hood. Packaging with CleanInstaller, I suppose? Will S2PCI not copy all the ‘bad things' like memories, SWAFs etc.?
4. Related: When I clean the character file(s), but copy and later replace my ‘saved Sims' folder, won't  this reintroduce this' garbage' or am I right in suggesting that these data are exclusively stored in the characters folder.
5. I'm a bit confused by this:
http://www.moreawesomethanyou.com/smf/index.php/topic,4090.0.html
(by Nec) That's an older post so I suppose I can ignore this and just follow the one mentioned before:  ‘Creating a Claen Custom Neighborhood' by Jordi?

I'm really very grateful for your help and the excellent tips I found over here. Awesome

O.k., make fun of me if you like, but in the past I've done some massive surgery on my townies, kept them in the bin and from there - deleted them afterwards. This was before I knew this was a bad thing to do. Now I've noticed that in SimPe all my Sims have memories of the dummies. It wasn't until some ‘Wants' turned blank (just no picture, the want were readable when hovering over) that I've started searching for an explanation and hopefully a solution. Even after doing a lot of reading I'm still not sure how to rescue my hood from becoming a BFBVFS.
Fortunately, I play my Sims much like in Sims 1 mode, they never marry, get babies and don't die, so I don't have to worry much about the DNA part (I think). Would it be enough to delete all the memories (in the SimPe's memories box) with the ‘nuke memories' option, or should I use the Lot Debugger instead. I have it installed but I don't quite understand all the options. Furthermore should I do some work on the SWAFs as well - I've noticed that in the SimPE box some Wants turned blank also.
Or, is this Neighborhood (Pleasantville) beyond rescue and should I go for the empty and cleaned templates that I read about.
http://www.moreawesomethanyou.com/smf/index.php/topic,4306.0.html
I hope someone will give me some directions. My EP's are NL and OFB. Thanks for any help.