[spoiler=] I am trying to kill Dr. Nefarious on his space station and the laser keeps frying me. Any ideas to make this one easier? I've tried everything I can think of and I'm dead about 30 seconds after it starts! Any help will be gratefully accepted. Thank you! [/spoiler]

That was the most frustrating part of the game for me, Lol.

All I can suggest is keep practicing. You of course need to equip the hoverboots and press R2 to boost. Hit every single arrow on the path that you can. Don't hold your jumps when the electric things come your way (the ones Nefarious rolls at you), but instead just have quick hops because you slow down way too much when you're in the air.

I found, oddly enough, I seemed to go faster on the outside of the track instead of the inside.

Other than that . . . I'd say keep at it, because that part of the game was the most frustrating for me with the jumps and all that stuff.

my advice, keep jumping. side jumping in fact (R2, jumping in either direction).

rule of thumb, when in doubt, JUMP!

As for the actual fight, my rule of thumb would be this:
STRAFE.
It took me about 3 or 4 deaths to remember to start using that again. Also, a good fully auto weapon (like the constructo pistol) and a weapon that causes flinching (such as the negotiator or Mag-net cannon) work really well for a quick switch team.

The chase sequence is a bit tougher, but I noticed (at least in my play-through) that Nefarious stuck to a side for a duration of the time. Find that pattern and do the opposite. When the track breaks apart, remember you can still hover (or whatever holding X is called) to a floating piece if you miss a bit.

This is just somethings I picked up on. Hope it helps.