under Linux things are just a little bit slower
Are we talking a HD install or running off the CD?

If off the CD, the best thing you can do is to resize your Windows drive and create a Linux swap partition. This'll speed things up a bit: you want something in the order of 1/4 to 1/2 gig (nothing more).

If we're talking of a hard drive install, then, at a GUI level, Linux will always appear to be slower than a Windows 9* system built on the same hardware. But the appearances are very deceptive: it'll multi-task properly and stuff like compiles and file transfers will work far faster.

The obvious process for extermination (assuming that you're using SMTP from your ISP) is smail: use the SysVinit editor (Kmenu > system > SysVinit editor) to despatch it. You'll probably see a lot of other services you don't need, but ask here first!