Corolla 1.3 1994 - Advice Please

[nice]

Just bought this old lady from a mate of mine, it's a Corolla GLI Auto 1.3, 1994, 150,000 miles on the clock, but starts like a dream. The only problem at the moment is that getting into first gear is very sloppy, it over-revs before engaging, same with second gear. I'm having it serviced at the weekend and have explained all this to the mechanic, who thinks something in the gear mechanism is slipping (forgot exactly what he said). Petrol consumption is pretty dodgy as well, but I'm presuming that could improve after the service (plus, air in one of the tires is very low, I've just noticed, which could explain that).

I was just wondering if there is anything I should be asking the mechanic to specifically look at? I read in another post someone suggesting the following things to get or check, to a guy who had a Rolla of the same age/type as mine (automatic):

new original spark plugs

new spark plug cables

distributor cap

rotor

air filter

fuel filter

pcv valve

correct wheel alignment

tire balance of all wheels

check the ignition timing

idle speed has to be set correctly

Will the mechanic be naturally mindful of the above or should I specifically ask him to take a look at 'em? The mechanic also asked me to bring a bottle of slick 50 when I drop the car off for him to work on, I've read a bit about it online and some people say not to use it, would it be good for my car?.

My knowledge of cars is pretty limited, so if anyone has any other advice on how to keep this little baby running for another 100,000 miles, I'd appreciate it. I bunged my mate £100 for it, so I want to turn it into the bargain of the century by seeing it run for a few more years.

Cheers for any help you can give.