"I want it to be Friday today."
Translation:Jag vill ha fredag i dag.
På torsdag äts det ärtsoppa, på lördag är det fest
Men fredag är ändå den dagen som känns bäst
Ge mig då kyckling, det gillar jag mest
Kyckling på fredag, det enda jag vill ha
Kyckling på fredag, då mår man riktigt bra
Kyckling på fredag, vad var det jag sa?
Jag vill ha fredag i dag!
I think the Swedish sentence should be accepted, as it is, but I feel there's some logical contradiction in it. The English version sounds even worse to me, "I want that it is Friday today", is probably not an acceptable sentence. But I'll leave that up to English native speakers.
It isn't an acceptable sentence for lack of the use of the subjunctive form of "to be." A correct sentence would be:
"I wish that it were Friday today."
Increasingly people are using "was" in place of "were," so a sentence like
"I wish it was Friday."
is likely to be heard and accepted, even if it isn't yet technically correct. Given English's propensity to change, I wouldn't be surprised if in some number of years this form becomes considered standard and were antiquated. It is, after all, how the language goes.
"Idag" is probably a bit more common these days, at least in informal written conversation. "I dag" is what the Swedish language council recommends, and it's also the form used by e.g. newspapers. Both are accepted. Same with "i går", "i morgon", etc. (but not "i år" - "iår" would be a mistake!).