Look up your the VAG oil spec for your car (you can get it easily by putting your reg no into an oil finder (I like Opie's as that's where I buy my oil). For my 2016 CHZB engined
Ibiza its a 5W-30 to VW 504. So any brand that complies with that spec would be safe although I'm a bit "anal" about this sort of thing and like to stick with what I've already put in at the oil change to avoid any possible weakening of additive package strength. The fixed/yearly interval service - I don't "do" extended service intervals - recommendation for my engine is a 5W-40 to VW 502. The "40" figure in the SAE spec (5W-40) means that it will be a little more viscous at working temperature so might cut oil consumption a little.
I'm about to do the first service on my
Ibiza now it's out of warranty. The dealer tells me it's been filled with Castrol whilst it was serviced by them during the warranty period so my inclination was to carry on with their Edge Titanium 5w-30 LL but the quoted service oil fill is 4 litres and Castrol supply in 4 litre containers so leaving nothing for the occasional top up or a wee bit for doing door hinges, locks, and other. I've used Fuchs on many occasions - both the family Fiats are running on that brand at this minute - and they supply their Titan GT1 Pro C-3 SAE 5W-30 XTL (what a handle!) which is VW 504 compliant in 5 litre containers and at roughly the same price as Castrols "premium brand" price for their 4 litres. After havering over this for some time I've decided, last night, to go with the Fuchs! During my investigations I've discovered a lot about Fuchs I didn't previously know and it's impressed me deeply. One of these facts, which I haven't investigated in great depth because at this time it's not relevant, is that they do their "Race Pro" range. This might interest you as I think it uses a very sophisticated base oil - Ester?) and is particularly aimed at high performance engines. Try asking Opie about it either, on line or give them a ring, I find them very approachable and knowledgeable.
As said above I would do an air and oil filter every year - you might get away with every second year with the air filter if you don't do many miles - as I'm only doing 5 to 6,000 miles a year now I'm thinking about this - but do the oil filter every time you change the oil. I was surprised to find there is no recommended interval for the fuel filter. My local indy actually said to me "If it's not leaking just leave it alone"! I'm not all that happy with this so think I'll be changing mine every 5 years when the cam belt gets changed. It looks easy enough to do (the filter that is) just some plastic unions to compress and pull off. I believe the unions are not available separately so be a little careful when compressing as you have to renew the whole fuel line if you break/damage a clip.