best thing to do when you have a bad computer and your getting bad fps all you have to do it get a better pc

While yes, this is a good solution, some people are not in the financial position to do so.
The best adaptive thing to do for someone asking for optimization tips, is to just in general help them with features that use a lot of processing power. As Garry's Mod is a single-core application, you can't use all your processing power (unless you turn on the experimental multicore feature)

You should adjust your visual settings and disable the things that are useless, like skeleton for example, and add a max distance to filter those who are far away, though, this is only useful when there's a lot of people in the server.

Hold down spacebar, it should work. If not, try messing around with the settings a little bit.

The only thing funny with GMod now is:
1. People are stupid enough to recruit incompetent and immature players for their staff team.
2. Everyone lowkey trolls in DarkRP.
3. Most servers purchase their plugins and add-ons from GModStore, despite them being full of security issues.

I haven't seen it yet, but the old menu was really old, confusing albeit very unique compared to other providers.