First things first, post up the specifications of your Computer.
Textures and whatnot are great, but to get nice Graphics in LFS, you need the Hardware to do so.
You don't need much to run LFS nicely. I have a Computer at work with;
Pentium 4 CPU 3.2GHz
512mb RAM
80gb HD
256mb Nvidia 7600GS
Windows XP MCE
As you can see, it is not a powerful PC in the slightest, yet it runs LFS at 1280x1024 (32 BIT) with 8xAA (Anti Aliasing) and 16xAF (Antistropic Filtering) at 75-80FPS, and can handle around 10-15 cars (depending on the cars and track) before it starts to stutter. Basically, anything with anywhere near these sort of specs should be getting pretty decent performance.
So, once the Graphics and Resolution is sorted out, you need to move onto Textures.
Without sounding biased, Lynce (lfsn00b posted his link above) really is the best texture guy on the LFS scene at the moment. Pretty much any of his textures around bound to make an improvement, but the ones that really make a difference in terms of screen shots and general gameplay are his reflection packs. They truly are amazing, and make the game look much prettier.
Also, if your LFS install is too cluttered, i would recommend saving your important files (e.g, ones you do not want to search for again) like skins and pictures, and then delete the old LFS install and download a new one. It would not take long to do this and get it all setup how it used to be. I do this quite often if i find my LFS install is getting full of old skins or files.