If you want to set up a dedicated DOS session(s), create a start up (boot) menu - How to create a boot (start up) menu under Windows 9x/ME.
Just remember that under "real" DOS, you need drivers for your mouse, CD-ROM, memory manager, etc.

Before you do anything like configuring DOS menus, setting up drivers and such - answer this question: do you currently have DOS games that do not work (or do not work well) if you just run them from inside Windows 98 SE?

I think pure DOS can come later
for now i'd like to ensure i know how to best optimize 98se.

For Windows 98SE, I always install the Unofficial Windows 98SE Service Pack 2.1a (which basically includes a combination of all the official Microsoft patches). Installing the later Service Packs adds features that were not officially released by Microsoft.
I then extract (from one of the version 3.x Service Packs) the USBStack driver set that then gives me USB support for removable media.
I recall seeing a post a while ago of what other users recommend you install. If I find it, I'll post the link.
EDIT: What updates do you consider critical for Windows 98 SE?

Ooh thanks!!

jesolo wrote:

For Windows 98SE, I always install the Unofficial Windows 98SE Service Pack 2.1a (which basically includes a combination of all […]
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For Windows 98SE, I always install the Unofficial Windows 98SE Service Pack 2.1a (which basically includes a combination of all the official Microsoft patches). Installing the later Service Packs adds features that were not officially released by Microsoft.
I then extract (from one of the version 3.x Service Packs) the USBStack driver set that then gives me USB support for removable media.
I recall seeing a post a while ago of what other users recommend you install. If I find it, I'll post the link.
EDIT: What updates do you consider critical for Windows 98 SE?

You can get the USB storage driver separately. No need to mess with extracting from one of the later super buggy unofficial service packs.

Take note that the USB driver I'm referring to here is not "nusb33e.exe" - that driver has caused issues for me. I therefore use the USBStack.exe driver that is a separate file within the SP3.CAB file that forms part of the Unofficial Service Pack 3.x package.
A file extractor (like 7-zip) does the job.
If you know where to find that file separately, please do share.

It looks to me like there is quite a bit of complicated file organization for that. Is it difficult to do?