Your fuel filter must be like the one on my 2003 Toyota Sienna, it is part of the fuel pump assembly in the fuel tank.....not a routine change item.
THIS picture shows what the coil looks like on my Sienna.....the right-most coil is out.
IF you change the spark plugs, I would recommend that you stick with the EXACT plug number that is called for as Original for your car (Unless TOYOTA has updated their specification to another plug).
They may list a DENSO or NGK plug for your car.
Rockauto lists DENSO Iridium SK16R11 which has a Iridium center electrode and a platinum enhanced ground tab.
They also list DENSO PK16R11 which has a Platinum center electrode and Platinum enhanced ground tab.
I don't know which your car came with, but it will be one of those 2......although you should be safe using the Iridium in place of the platinum if it came with platinum.
Personally, I would AVOID the "peformance upgrade" (that you are unlikey to notice) of the DENSO IK16 plug with the 0.4mm diameter center electrode in place of the 0.7mm center electrode.
I did some reading on the DENSO website and found that DENSO rates the 0.4mm version for 30K miles whereas they rate the 0.7mm for "up to 120K Miles".
As for oil, if a non-synthetic oil was used, it is worth noteing that (in general) a non-synthetic oil has more evaporation than a high end synthetic oil.
More evaporation usually means more deposits as you see on the baffel under the fill cap.
I say "high end" because the line between "synthetic" and non-synthetic is quite blurred.
The good non-synthetic oils have come a LONG way over the past 10 years.
Also, as mentioned in one of the posts above, it was mentioned that the pistons run hotter in your Celica.
A synthetic oil generally has better heat tollerance.
Are the pistons running hot enough to NEED a synthetic?.....I don't know.
I use synthetic oil (Redline), which is way overkill for my application.
The oil that you show in your picture is well respected on this site and will serve you well.
To Bill-In-Utah's point, there are some very good non-synthetic oils out there and he has given you some good advice for your vehicle.
I would NOT run a non-synthetic for an "extended" oil change interval of over 5K miles in your motor.....however, you are not looking to do that anyhow.
I don't run synthetic for the LONG periods that some folks on here do, but then my 1MZFE motor is not known for doing well with extended runs with oil.
I have not used MMO so I have no advice to give with it.
I have used AutoRX in the past.....even with Redline in a "maintenance dose" based upon a old post by a member "Molakule".
However, I will be first to tell you that your vehicle does not require a $10 per quart oil.
I have read a number of posts on here that folks have put up about their experiences with MMO, and they would be better able to advise you.
Although 20% does sound a bit high for the MMO, I would prefer a lessor amount, like the 12% electrolover mentions.
You have selected a good oil, and you are trying to enhance its cleaning ability without reducing the benefits of the oil that you ae using.